After migration to new server, windows client can't connect

after successfully migrating a nextcloud installation to a new server and restarting the nextcloud windows client, this message appears and even after granting access, the client can’t connect. Is there a way to resolve this without any action on the client’s side?

Security warning If you are not trying to set up a new device or app, someone is trying to trick you into granting them access to your data. In this case do not proceed and instead contact your system administrator.

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moved it to clients as it may be a client problem?