Hi
Are you the hotspot owner or a user?
This kind of message (STOP_NOT_RCVD) happens when the hotspot did not send the stop request.
When worldspot does not receive alive messages for some time, it automaticaly change the state into STOP_NOT_RCVD
This generally happens when chillispot is restarted. People should know that everytime a dd-wrt setting is changed, the router is rebooted, loosing all current connections states, causing the stop request not to be sent.
Is this your case?
Hope this helps.