When trying to sign into the app I get an error message.
Sorry something went wrong
We're working to fix this as soon as possible. Check back later.
It's been weeks. I can sign in via website.
It's really hard to say what the problem could be.
I once had some problems with my account. Something got messed up on Rogers' servers that actually caused the iPhone app to crash. (I called tech support to report the problem, and it took a while to finally get fixed.)
Sometimes the app's local data storage on the mobile device gets messed up, and you can fix that by deleting the app, deleting the app's data, and reinstalling the app.