[2106401] The assigned Active Directory user account has to be disabled for this type of mailbox.

I ran into a problem. There is a person card in which there is an active directory account and a mailbox. We tried to change the attributes of the active directory account, but we get an error -The assigned Active Directory user account has to be disabled for this type of mailbox. we found out that this is due to the mailbox attribute (Mailbox type)- Linked Mail. The mailbox was not created by the system, but manually, the system subtracted it after synchronization. It is also not possible to change mailbox attributes. Maybe someone had a similar case?