I have an iPad (& an iPhone),
The MOST annoying thing about these is the difficulty if you can't remember your password, compounded with another issue. I tried every variation I could think of, all failed.
The "other" issue is that the email the App store has is no longer valid & I can't figure out how to change it. I suspect I can't change it without my password, so sounds like I'm in a catch 22.
Any way out of this?