Hi Emiliano

There isn't a way to merge a user's Record of Learning - having two accounts for the same user doesn't need to be used.

A user can be a tenant participant for more than one tenant and enrol in courses in any tenant they are a participant of and enrolled courses from different tenants  will show on their Record of learning  .

Please check on the list of partially supported and  unsupported features for multi tenancy.

Regards