On Exchange Online synced, you can create some dynamic groups. The first group is created with ECP. The set up is creating a separate group based on the city attribute in AD. More groups are created in the security section. This was done with the help of Powershell. But, the weird than that the group membership list does not show them.
This issue may be because of a wrong recipient filter. So, checking the filters is a must. Also, check the filters if they are correct.
Another solution is to use the MS Doc on the cmdlet. Fud the link here:
Written by: Owner