Connection Problem between Exchange E-Mail and Retention Labels Policies

Hi,

I want to set some Retention Label Policies for Outlook Web App for the members of my organization through the Microsoft 365 Compliance Center. All settings look good and theoretically everything should work properly, but there's no connection between the Retention Labels Policies from Compliance Center and the Outlook Web App, where I can't see the Retention Policies and there's no effect over the E-Mails (for example after 1 Day Delete). All Retention Label Policies are with Active status in the Compliance Center.

Could you help me with some ideas how to solve my problem?

Thanks in advance.