To merge users in Alma, your account will need the User Manager or User Administrator role.
You can set up a job to merge duplicate Patron user records into another user record. The merge moves all fulfillment activities (loans, requests, fines/fees, interested users and circulation history) to the new user record and includes an option to decide which segments to merge (contacts, Identifiers, notes, blocks, demerits, statistics, attachments and proxy for).
Select the Merge Users page (Admin > User Management > Merge Users).
When this process runs, the duplicate user is deleted. Changes are permanent. To undo you would have to manually re-create the merged user.
Please see this link for additional Ex Libris documentation: https://knowledge.exlibrisgroup.com/Alma/Product_Documentation/010Alma_Online_Help_(English)/050Administration/030User_Management/70Merging_Patron_Records