not able to see any option to associate devices on Custom OID

Hi Team,

I have added a custom OID of CRC error which i want to monitor.

but i am not able to add or see any option to add a device on Custom OID or Associate Cutomer OID to any device.

As per document i have check both option to add or associate device on Custom OID but i did not see any option for that. Please find snaphot for your reference

Kindly help me on this