Sorry but I don’t understand what you talking about.
I’ve got Cisco AIR-AP1702I-E-K9 for example which I can monitor throught the WLC2504 but not through the WLC9800.
Here is the complete name of the controler : Cisco Catalyst 9800-40 Wireless Controller
running latest IOS-XE version : 16.12.4a
It seems this WLC is not recognized and the plugins cisco_wlc and cisco_wlc_clients nat not used yet.