Hi there! Sorry to hear you're having trouble logging into the OS Maps app on your iPhone. That "Have a problem, try again later" message usually indicates a hiccup connecting to the server or an issue with your login details.

To help you out, could you please confirm a couple of things for me?

1. Are you entering your email and password correctly?
2. Have you tried restarting the app or your phone yet?
3. Are you connected to a stable internet connection (WiFi or cellular data)?

Meanwhile, here’s a simple step-by-step you can try:

1. Close the OS Maps app completely (swipe it away in the app switcher).
2. Restart your iPhone to clear any temporary glitches.
3. Open the app again and attempt to log in.
4. If that still doesn't work, try using a different network (switch from WiFi to cellular or vice versa).
5. If possible, check if you can log in via the OS Maps website on a browser to confirm your account is working fine.

If none of these help, let me know if you've tried resetting your password already or if you get any other error messages. We can dig a bit deeper from there!

Are you happy to try these steps and update me?