Unable to synchronize with application


I have a problem with my Nextcloud server since I switched to version 12,
all the accounts that I create it is impossible to do synchronization with PC or Android application but no problem with my old accounts.

Thank you in advance for your help

Do you have 2 step authentication turned on? It is prohibiting all of my webdav services to not sync (contacts, calendars, tasks, keepass)

I have a hard time expressing myself.
I have a problem synchronizing the personal folders of each new account.
thank you for your reply