The Merge Profiles tool serves to unify two duplicate profiles. You must take into account that it is an irreversible process. That is, once you have done it, you will not be able to recover the unified profile again.
To merge two profiles, you have to access the profile whose data you consider correct and, once inside, click on "Options">"Merge profiles":
You can then search for the profile or profiles you want to merge to the selected one. You can search by name, surname or ID.
Once the two profiles have been merged, all profile, license and participant data of the correct profile will be kept and only license or participant data will be added.