The API_NO_MEETING_RECORD_FOUND error generally occurs when you are trying to join a room that has already expired. 

A room generally expires after the startTime and duration is set and after the duration is completed. You can set the duration of the room under the credentials field of the init method 
The default expiry time for a room is 24hours. 

See here for corresponding android method used to generate credentials. See here for iOS.

The simplest way to create dynamic rooms is to configure your key in the Temasys Console to ensure that the Persistent Room field is set to No which is the default option.