After updating to iOS 15, I got error message 0-10001-1 when trying to open Elder Scrolls Blades. The error message screen is above.
I waited and tried again. This time I got another error message (above) telling me to either retry logging in or to continue on and set up a new character. Retrying did nothing, so I set up a new character. You'll have to accept the game conditions again and go through the brief movement tutorial, then choose a name and attributes for a new character. At the end you have the ability to log into Bethesda again with your old character name/login, so do so. (DON'T skip logging into Bethesda or you won't be offered the choice of either character, which you need to retrieve your old character.). Once you do that, Bethesda will tell you to pick either the brand new character or your old one. Pick the old one and you are set.
Note that some folks on Reddit say that powering down their device and then powering it on again and attempting login to Elder Scrolls Blades fixed their issue. This didn't work for me.
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