If you have a vlan in vmware that contains a / in the name, then netbox's imported vlan name on the VM interface will show %2f instead of /
2020-11-18 22:37:23,796 - DEBUG: Ip address '10.32.0.200/24' attribute 'assigned_object_id' changed from 'None' to 'vNIC 1 (2000-management-10.32.0.0%2f24) (sv1-vcenter)'