Smbclient server error

I had several SMB connections setup inside Nextcloud and it worked fine.
I now had to move my Nextcloud server to a different subnet but the Nextcloud setup still points to the old server addresses and constantly brings error messages in the Nextcloud logs.
Unfortunately I cannot log into Nextcloud to make changes.
How can I disable smbclient or amend the server address pointers manually in the CLI?
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