Monitoring client connections on a cisco C9800-CL with 2.0.0p17 (CRE)

Hi,
I’m back with strange news. The MIB on the C9800 is the same as the others so I don’t understand why it’s not working !
When I do snmpwalk -Of -v1 -c <community> <ip> .1.3.6.1.4.1.9.9.512.1.1.1.1.4 I have the three SSID.

.iso.3.6.1.4.1.9.9.512.1.1.1.1.4.1 = STRING: "<SSID1>"
.iso.3.6.1.4.1.9.9.512.1.1.1.1.4.2 = STRING: "<SSID2>"
.iso.3.6.1.4.1.9.9.512.1.1.1.1.4.3 = STRING: "<SSID3>"

And when I do snmpwalk -Of -v1 -c <community> <ip> .1.3.6.1.4.1.14179.2.1.1.1.38, I have the number of connected clients.

.iso.3.6.1.4.1.14179.2.1.1.1.38.1 = Counter32: 87
.iso.3.6.1.4.1.14179.2.1.1.1.38.2 = Counter32: 3
.iso.3.6.1.4.1.14179.2.1.1.1.38.3 = Counter32: 21

My question is : what is wrong with my configuration ?

I hope somebody could help me !

Thanks.

Have a nice day,
Jean-Emmanuel