A return trip request is for a return ride from the destination back to your pick-up location after a period of time. This is NOT the same as a roundtrip, and will automatically place a second ride request for the return trip.
Because two separate requests will be entered, one to your destination and one returning from your destination, it is possible that it may not be the same service provider for both trips.
To make sure both rides are with the same service provider, you must specify the service provider and select 'cancel my reserervation' under 'ADDITIONAL DIRECTIONS' on the confirmation page.