Hi
Just wondering what's the method you are using to transfer the records?
also how did you provision the Portals? if you provisioned differently that might have caused you to have different Portals types - thus different Website GUIDs
if you can re-provision the Portals would be better, otherwise you will have to re-associate every Portal record (web pages/entity forms/etc) to the new Website record
------------
If you like this post, give a Thumbs up. Where it solved your request, Mark it as a Solution to enable other users find it.