It's not clear wether your AP is not broadcasting the SSID, or if your client can not see the SSID.
We are indeed having problems with AP 515 with HE turned on.
This is due to old firmware on Intel NICs.
Turning of HE made the SSID visible.
Updating the driver also made the SSID visible, with HE on.
Doing "show ap bss-table" should confirm that your AP is broadcasting the SSID.