Some UIDs are customizable. To do so, click on the 3 dots next to the UID and choose 'Edit'.
Depending on the type of UID, the data may or may not be changed (e.g. from/to, value).
Note: Some unique IDs are not editable via MyMip for security reasons. E.g. a UID from an external system (e.g. POS system) cannot be removed or changed, because a contact can then no longer be found in that system or a wrong connection is made.