How to turn of 'tracked in dynamics 365' category

Hello

For my job we work with a shared mailbox for which the rule is set that all Email messages from Dynamics 365 Lead, Contacts and Accounts are automatically tracked in CRM. However, since this weekend, an automatic Outlook category "Tracked in Dynamics CRM" has been created in which all tracked emails are stored automatically. This is not what we want because we work in a different way with categories in the shared mailbox. 

Is there a way to turn off this automatic transfer to the category "Tracked in Dynamics CRM"? We"ve already tried to delete the category but it autocreates itself again.

Thanks in advance!