This article discusses how to remove license from a Direct Routing User.
Recoup the License from DirectRouting User DirectRouting User After Direct Routing Setup
DO NOT CHANGE the DirectRouting User until the Direct Routing Setup has been fully confirmed as complete.
The following instructions are available in video form here.
Navigate to the Microsoft Admin Center >> Active Users and select DirectRouting User.
Select Licenses and Apps
Unselect the User License and if relevant the Phone System Add On. In the example below E3 and Microsoft 365 Business Voice. You can use any combination of compatible licenses listed here.
Select Save changes.
On successful removal of licenses, you will see a small notification on your DirectRouting User Licensing page. You will also see that the DirectRouting User will be considered Unlicensed.
DO NOT DELETE the DirectRouting User.