MAC Address lookup not working

This is probably a stupid question…
Under the client list when you mouse over a MAC Address, it used to show the Vendor of the MAC/NIC but now all I get is a spinning circle.
I have been looking for the fix to this issue on and off for over a month and figure I may as well just ask and see if anyone knows where to fix that.
Thank you in advance!

The feature works for me. Occasionally a device won’t show a manufacturer if the look-up information is not available.