This is likely to be because you do not have your GPS settings enabled. As RingGo's mobile apps use your devices GPS position then you must ensure that this is turned on prior to searching a location via the app.
For iPhone: Select 'Settings' then 'Privacy' followed by 'Location Services' and ensure that this is set to on for RingGo.
For Android: Select 'Settings' followed by 'Location' and ensure 'Use GPS Satellites' is set to on.
This should then allow you to search all RingGo locations by either location code, location name or by finding nearby locations.
If you are still unable to return any locations then we would recommend uninstalling and reinstalling the app. This will force through all recent updates and should return the app to normal functionality.