Subscriber manager is not working without license on vMX newer than 18.
Same is true on 20+.
But with license you've provided it will be working. 😁Just checked it:
root@vMX1> show dhcp server binding
IP address Session Id Hardware address Expires State Interface
16.16.110.2 35 80:26:89:11:59:bf 39 BOUND ge-0/0/3.3221225486
root@vMX1> show version
Hostname: vMX1
Model: vmx
Junos: 20.1R1-S2