Can't assign primary IP when editing and assigning existing IP address

[arthanson]

NetBox version

v3.6.2

Python version

3.8

Steps to Reproduce

1. Go to an existing IP address
2. Assign the address to an interface
3. Check "Make this primary IP for device/VM"
4. click the Save button

Related to: #12953 - but this is for editing case, not create case.

Expected Behavior

IP Address will save without error

Observed Behavior