I am willing to bet that you are a Lync/Skype for business user at the office
If you have any contacts in Lync/SfB in the other or favorites group they get added to a contact group in Exchange called Lync/SfB contacts. Those contacts are not properly formated entries and you can not edit them.
Your contacts are syncing with Exchange that that "Lync/SfB Contacts" group is synced as well.
To fix it you can either, remove all contacts in Lync/SfB that are not in an Outlook Mail Group or you can go to contacts on your phone click groups and uncheck the Lync/SfB Contacts list.