LDAP Users Migration

Hi I have Nextcloud 15 installed with users IPA authentication.
Recently we migrated our new IPA to the newer version 3.0 .
Usernames are the same on the old and new IPA servers.
I tried to add the new LDAP configuration in nextcloud for the new IPA sertver and then I deleted the old LDAP configuration for the IPA server from nextcloud.
After that users were not able to login to the nextcloud .
We would like to retain the users from the old LDAP configuration for the new LDAP configuration. Is there any way we can achieve this ?

Thanks
Marcello