Hi. I have a 1password subscription . I created a new login but unfortunately had it open on both an iphone and ipad while editing and it caused a sync problem (two different entries on two devices [not duplicated]). I tried to fix it by renaming etc but the ipad ended up out of sync with my other devices. After quitting and relaunching the app a few times with no success, I then tried completely logging out of my 1password account on my ipad, closing the app and relaunching. I now have to re-input my 1password.com details, selecting the account it previously found but am told "A problem with your sign in. Please check your Master Password or sign in manually with details from your emergency kit or a signed in device" (this message is on the ipad iOS app to be clear). I am definitely typing in the password correctly and it's working on other devices and at 1password.com. I could try deleting and reinstalling the iOS app (which I think I will do anyway) but perhaps you have some bug somewhere in your sync method that is causing this as this seems like quite a big problem when all i did is have the same login open on two devices (displayed on one and edited on the other).
1Password Version: 7.3 (iOS)
Extension Version: Not Provided
OS Version: iOS 12.3
Sync Type: 1Password account