looks like a similar topic like this
https://dietpi.com/forum/t/help-wifi-hotspot-on-same-subnet-and-ssid/4023/1
UPDATE
Well, Hotspots that is provided as software in DietPi should work same way like raspap.
looks like a similar topic like this
https://dietpi.com/forum/t/help-wifi-hotspot-on-same-subnet-and-ssid/4023/1
UPDATE
Well, Hotspots that is provided as software in DietPi should work same way like raspap.