Troubleshooting common problems

Something not working as expected? Find your problem below. Each one says what is happening and what to do. If nothing here helps, report the problem — MonstarX captures the page for you, so the team can see what you saw.

My build is slow or looks stuck

A small change takes a minute or two; a whole new app usually takes several minutes. While MonstarX works, the chat shows a live line for each stretch of work with a clock, and — until there is a page to see — the preview shows a status card with what it is doing now, for example Writing code… · 7 files. If those lines keep changing, the build is working. See Follow a build.

What you can do:

• Close the tab if you like. Builds run on MonstarX, not in your browser. Turn on notifications to be told when it is done.
• Check the queue. Requests take turns. A Build request sent while another build runs waits above the prompt box under Up next and starts by itself. If it says Queue stopped (for example after you pressed Stop), click Resume. See The queue.
• A silent model is handled for you. If a model stops answering, MonstarX moves the work to another model — the chat says … stopped responding — continuing on ….
• Still nothing after a long wait? Click Stop, then send the request again, or pick a different model in the model picker.

“MonstarX stopped after … steps”

One request can take only so many steps. A very big request can reach that limit before it is done. Everything so far is saved. Click Continue (or Continue building, when planned features are left) and it picks up where it stopped. See The feature plan.

“MonstarX restarted while this was being worked on”

MonstarX was updated during your request. It carries on from the last step by itself — you do not need to do anything. If you instead see MonstarX could not start on this request, send the request again.

My preview is blank, asleep or showing an error

1. “The preview is asleep” — a preview stops after 20 minutes without use and shows a saved copy of the page. Move your mouse over the workspace, click anything on the copy, or click Wake it now. It starts again in a few seconds.

2. “Starting the preview…” — the first start sets up a secure cloud computer for your project and installs what the app needs. It can take a minute.

3. “The page is not rendering” or “Getting the page back…” — the page is empty or has an error at this moment, often because a build is halfway through writing it. MonstarX reloads it by itself as soon as the code works again.

4. Still blank or out of date? Click Reload preview in the preview’s toolbar. If that does not help, click Restart dev server (on a phone: the ••• menu → Restart the dev server).

5. “Reloading has not helped” — the app itself has a bug. The page’s error is shown below. Ask in the chat, for example: “The home page is blank — please fix it.” A fix from the chat takes over on its own.

If the project was shared with you to view, you can Reload the preview; if it keeps failing, ask the owner to restart it. More in Preview.

I see “Something went wrong”

That page means MonstarX could not open what you asked for.

1. Click Try again.

2. If that fails, reload the page, or click Home to start again from your projects.

3. Still failing? Check your internet connection, then report the problem.

Related messages and what to do:

Message	What to do
MonstarX has just been updated. Reload the page to carry on.	Click Reload. A new version of MonstarX came out while your tab was open.
MonstarX was updated while you were working. Check whether your request completed; if not, try again.	Look at the chat. If your request did not finish, send it again.
Could not reach MonstarX. Check your connection and try again.	Your connection dropped. Reconnect and try again.
Your message is … characters over the 100,000-character limit.	Shorten the message. The box shows a count as you get close.
This model is unavailable on your plan.	Choose Auto or another model in the model picker. Premium models need Plus or higher. See Choose a model.

I hit a usage limit

You see You’ve used your 5-hour limit on the … plan. It resets in … (or your weekly limit). Nothing is lost. You can:

• Wait — click the usage ring beside the prompt box to see when each limit resets.
• Use a Boost to reset every limit now (Plus and Pro only).
• Upgrade for bigger limits straight away.
• Premium allowance used up? Pick a model from Lower cost or Standard and keep building.

When there is room again, ask MonstarX to continue. See Usage and limits.

I keep getting signed out or sent back to sign in

Coming back from Stripe, Google or a link in an email, MonstarX quickly re-checks your sign-in; the page may flash once. If you end up on the sign-in page again and again, or see You were signed out. Sign in again to keep following this project:

1. Reload the page.

2. Make sure your browser allows cookies for monstarx.com — signing in needs them. Strict privacy or ad-blocking extensions can block them.

3. Sign out from the menu under your name, then sign in again.

4. Try a private window or another browser. If that works, an extension or a browser setting is the cause.

Forgot your password? Click Forgot password? on the sign-in page. See Profile and sign-in.

My domain is not working yet

A domain is your app’s own web address, like brewandbean.com. Its state shows under Domains in the project’s Publish menu, and in Settings → Domains.

State	What it means	What to do
Being registered	A domain you bought is being registered and set up	Wait. It is usually live within minutes, sometimes a few hours.
Setting up / Waiting for DNS	A domain you own is not pointing at your app yet	Add the CNAME record shown in Publish → Domains at the company that manages your domain’s DNS (its address settings). Changes can take a while to spread.
Issuing certificate	The address points at your app; the HTTPS padlock is being set up	Nothing — it goes live on its own.
Needs attention / Setup needs attention	Something did not finish	Open the app → Publish → Domains and press Finish setup, or follow the steps shown.

Also check that the app is published — a domain needs something to show. A root domain you own (like example.com rather than www.example.com) must have its DNS on Cloudflare; to keep your current DNS company, connect www instead. See Connect a domain you own and Buy a domain.

Emails from my app are not arriving

Your app sends email (sign-up confirmations, password resets, order receipts) from its own address on monstarx.app.

1. Open your project’s Backend›Emails. It lists every email the app sent, with its Status.

2. Not listed? The app did not send it. Ask in the chat, for example: “Send a confirmation email when someone places an order.”

3. Not delivered · test address? Addresses like someone@example.com can never receive mail, so they are skipped on purpose. Test with a real inbox of your own.

4. Failed? The reason is shown next to it. If the app reached its hourly or daily email limit (shown at the top of the list), wait and try again.

5. Sent but not received? Ask the person to check their spam or promotions folder.

See Email in your app.

QA keeps failing

Automated QA tests your app in a real browser. When a test fails, QA explains what went wrong in the chat.

• By default QA only reports. Choose Fix this problem (or Fix these … problems) to have MonstarX change the app and test again, or Later to leave it.
• Auto fix (in QA’s settings) fixes and retests by itself, but uses more credits.
• “Please check this yourself” — QA could not test a step. Open the preview, follow the steps shown, and tell the chat what you see.
• ”… is not connected, so that step was not tested” — the app needs a service, such as Stripe, that is not connected yet. Click Connect … on the QA card, add its keys, then run QA again (see Connectors).
• “QA was interrupted by a restart” — open QA in the top bar and click Run QA now.
• “Could not start QA” — QA uses your plan’s usage too. If you have reached a limit, see I hit a usage limit.

See QA testing.

A change broke my app — how do I undo it?

MonstarX saves a version of your app’s code every time a build changes it, so you can always go back.

1. In your project, click Versions in the top bar.

2. Find the version from before the change — each shows when it was saved and how many files it had.

3. Click Restore and confirm.

Restoring replaces the app’s code with that version. Your app’s data — users, orders, posts — is not changed, and the restore is saved as a new version, so you can undo it too. You can also tell the chat what went wrong: “Undo the last change to the menu page.” See Versions.

Notifications are not arriving

Turn them on for each device in Settings›Notifications and click Send a test. On iPhone and iPad, add MonstarX to your Home Screen first (Share → Add to Home Screen) and open it from there. See Notifications.

Frequently asked questions

Why is my MonstarX build taking so long?

A whole new app usually takes several minutes. The chat and the status card show what it is doing now; if that keeps changing, it is working. You can close the tab — it keeps building — and turn on notifications to be told when it is done.

Why is my preview blank?

Usually the preview is asleep (move over it or click Wake it now) or a build is halfway through writing the page (it reloads by itself). Otherwise click Reload preview, then Restart dev server, or ask the chat to fix the page.

How do I undo a change?

Click Versions in the project's top bar, find the version before the change and click Restore. Your app's data is not affected.

Does a failed build use my credits?

Yes, for the AI work it did before it stopped. The work is saved, so continuing does not redo it.

Who do I contact if nothing here helps?

Report the problem from Ask Luna (Report a bug with screenshots) or open a ticket in Support from the menu under your name. See Report a problem.

Related

Report a problemSend a bug report with screenshots, or open a ticket.

Usage and limitsWhat happens when you reach a limit.

VersionsGo back to any earlier version of your app.

PreviewHow the live preview works, sleeps and restarts.