I deleted an account in Settings > Passwords, but the app still default to that account
I have two apps on my phone, including Wells Fargo and a healthcare app, where I set up the apps using one username/password account, and then I needed to use a different account. I've deleted the original accounts in Passwords in Settings, and the new accounts are the only ones listed there. But every time I open either app, it actually logs all the way in under the old username/password.
Where is that data being stored? How can I really delete these old accounts and default to the new ones?
I've tried deleting and re-adding the apps themselves. I'm running iOS 15.5.
iPhone 11 Pro, iOS 15