Thanks for the suggestions.
I’ve tried deploying again after fly apps restart but it’s still not working.
My Account Status is Good Standing, so that’s not the issue either.
EDIT
I did a bit of trial and error, but still no luck. Here’s what I’ve tried:
fly apps restart
fly deploy → Unsuccessful, same problem
deleted all apps
fly launch → Successful deployment
made some changes in the code
fly deploy → Unsuccessful with error:
Updating existing machines in 'my-app' with rolling strategy
[1/2] Updating d89169da440438 [app]
Error: failed to update VM d89169da440438: You have reached the maximum number of machines for this app.
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deleted all unused / destroyed apps
fly launch → Unsuccessful because db wasn’t ready in time for some reason
deleted everything again
fly launch → Unsuccessful. Problem: Cannot deploy because of insufficient memory - #48 by andie
deleted everything again
fly launch with other region → Successful
made some changes in the code
fly deploy → Unsuccessful
So in the end the same problem remains.