Email change, old email populates automatically when I try to update apps

I think you may be right, it was done at the phone store where I thought we were updating my email address on my existing account (which changed because my server changed and the old address no longer exists. Maybe it wasn't done the way I thought it was though because it did mess things up. The iPhone upgrade that required the information transfer was done in the same timeframe as the email change so it transferred my data with the wrong information - darn. It does work when I delete the apps and reinstall them and that's what I've done for quite a few of them but some are more complicated and I'd rather not delete them because one in particular requires approval and video proof of identity to redo - as I said - complicated - I can't use it now though because it says it requires an update. I was hoping to avoid deleting it along with the rest of the ones left because they are more work to redo but I guess that's my only option at this point. I logged into Apple with my old email address but can't update anything because the information I'm trying to input is already in use. I guess that's that then - nothing I can do?

You are a genius. I tried the family sharing option and it worked so I can update all my apps. Thank you so much, I am so appreciative of your suggestion.