Freestanding propane stove won't stay lit?

We have a Lopi Northfield freestanding propane stove in a rental we own. When I turn on the wall thermostat, the pilot light comes on, the flame fires up a few seconds later, then the flames go out and there is a clicking sound which I think is the pilot light trying to restart. What can I do to keep the flame on? There is nothing in the troubleshooting section of the manual that deals with this particular problem, the dealer is very slow to return my call, the manufacturer has no service phone number and our renter is ready to move in! HELP!