Can't assign direct routing phone number to resource account using Microsoft 365 E5 Developer licens

Recently you can no longer assign a direct routing telephone number to a resource with an E5 developer license. 
Unfortunately, I don't have a Microsoft Teams Phone resource account license available. 
That's why I can't test all the possibilities of the auto attendant.

The following error is reported: 
User '13fcea9c-1968-4531-bb3a-dc660412d6f8' lacks appropriate licenses to assign a 'DirectRouting' number.
Licensed is "Teams Phone".
What can I do?