Possibly opened the valve too fast ? Try to reset .
1. Turn off the gas at the propane tank
2. Disconnect the hose from the propane tank
3. Open the lid of your BBQ Grill
4. Turn all the burner valves to high
5. Wait for 2 minutes (just time enough for a soda)
6. Turn off all the burner valves
7. Connect the gas line back up to the propane tank
8. Turn the gas on slowly on the propane tank
9. Light the grill using your normal lighting procedures
If the regulator was stuck, it should have been reset using these steps.
If you always turn off your burner valves first before turning off the gas at the tank, you will keep the regulator from sticking again.
More suggestions in the link …..
https://www.beeradvocate.com/community/threads/bad-propane-regulator-resetting-it.18601/