I will need a bit more information,
what did you setup as dhcp server, if AP it self , you may wnat ot check using a web browser the actual setup.
what switch did you use?
How many vlan on the switch ?
did you, or do you have to setup an IPhepler to forward udp packets to the AP.?
did you try with fixed IP addresses ?
so many question I know, but to help you I need to see your configuration.
please copy and past outputs of CLI configuration.
hang on, it will work