iPad files app remembers wrong login info

There are several categories of AutoFill - that derive information from different sources. They can be individually enabled/disabled and configured as required.

AutoFill of Credit Card and Contact Info within Safari

Settings > Safari > AutoFill > Use Contact Info

Settings > Safari > AutoFill > Credit Cards

AutoFill of your own details are derived from your Contact list. Ensure that you have set-up your own details as a contact - and then select your own Contact Card:

Settings > Contacts > My Card >

Your own Name should be shown here; ensure that you have selected your own Contact Card from your Contacts list.

Password (and Username) AutoFill

Settings > Passwords > AutoFill Passwords > AutoFill Passwords

Your saved website credentials, that you use for Password AutoFill, can be sourced from either your Apple Keychain - or other sources, such as Password Managers or third-party web browsers (such as FireFox or Chrome). Check that you have only enabled the source(s) that you wish to use.

If sources other than your iCloud Keychain have been selected, you’ll need to check the password stores for each of the other selected sources.

Assuming that you only wish to use your Apple Keychain, ensure that only this item is selected in the list of possible sources. With this verified, you’ll need to check the stored credentials for a specific website login.

Settings > Passwords

Using the Search dialogue a the top of the page, enter the name of the server/website that is causing difficulties. One or more entries may appear in the [now filtered] list. Check each one individually - ensuring that the Username, Password and Website (Server) are correct. If any errors are detected, you can try to manually correct the entry using the Edit function - or, perhaps simpler, delete the entry (having first made a note of its details).

Now, try to sign-in to the website/server resource - if AutoFill credentials are offered, you can try them. If AutoFill credentials are not offered (as you have previously successfully deleted them), enter the correct details; at this stage, don’t save them to your Keychain - as the object here is to prove that the manually entered credentials are correct.

If login is successful, you can sign-out, then repeat your login - this time saving the [known good] credentials to your Keychain.

It sounds like a DHCP problem, but it's not that easy to diagnose that kind of issue remotely.

I would contact your IT admin/supervisor and ask him/her to check your server DHCP settings for your iPad.

Regards

Giulio