Hello Charles
Cisco devices have traditionally supported two encapsulation methods: ISL and dot1q. Newer switches no longer support ISL, so there is only one encapsulation method available. For this reason, the switchport trunk encapsulation command was removed. This is the reason you don’t have that option in your device.
Is everything else working correctly in your topology or are you facing other difficulties as well? Let us know…
I hope this has beenhelpful!
Laz