@xpresso2780 User IDs cannot be merged. They are two separate profiles in SAP Concur. All you can do is deactive the profile you don't want to use. Before deactivating, have the user go in and delete any reports. Then deactivate the profile. The user will need to recreate the reports they deleted from the now deactivated profile.
Since your company is doing all expenses as out-of-pocket, this should only take the user a few minutes to recreate the reports they deleted from the deactivated profile.