Azure AD Synced group not showing members

I’ve had Duo syncing from my 365 tenant for a while now using a group that all of my users are a member of. I’m setting up the AWS application now which is only going to be available to a handful of users. I’ve created another group (AWSUsers) in my tenant and added those users to it. The group syncs to Duo fine but it doesn’t have any members in it. Can you not have 2 synced groups that contain the same users? How would I isolate the AWS application to a handful of users?

Never mind! The group membership updated overnight.