Not able to create Child Devices

[abhilashchinthalapudi]

Environment

• Python version: 3.6.8
• NetBox version: 2.7.1

Steps to Reproduce

1.Choose Create a Device
2.Choose A Device Type which is a Child Device
3.Click Create
4.The exceptions appears if no Rack face was selected and if rack face was selected there is another exception which is what it supposed to be Child device types cannot be assigned to a rack face.

Other Issues I am seeing is We are able to update custom fields as well with the below exception
from pynetbox
The request failed with code 400 Bad Request: {'face': ['Child device types cannot be assigned to a rack face. This is an attribute of the parent device.']}

Step to reproduce:
device.custom_fields['Invoice Number'] = 1234
device.save()

Expected Behavior

Child Devices to be created
Custom Fields to be updated

Observed Behavior

Child Device Creation Failed
Custom Fields Value not updated with above exceptions