I am running RouterOS 4.10 and attempted to set up a Virtual AP using the same settings as the default wlan interface but am having some problems.
I have an external DHCP server and have both the WLAN and VAP interface set up as DHCP relays. The WLAN interface is configured as 192.168.1.1/24 and the VAP as 192.168.2.1/24.
Whenever a wireless device attempts to connect to the VAP interface the DHCP server receives the requests and sends the response, but I see no indication that any packets have been transmitted out the VAP interface (tx counters remain zero).
I have no problems with the main wlan interface.
Both wireless interfaces are configured to use WPA2-PSK and the same security profile.
Check if mac winbox sees your router from the wireless connected device, to check for connectivity.
If so, then you try setting up a dhcp server on the interface directly ( on the vap, meaning ), and see if you have connectivity.