Sprinkler heads pop up crooked
My sprinkler heads come up but the ones that are 1/2 circles are spraying crooked. They spray a quarter of the lawn and a quarter of the driveway. I took pliars and twisted the black pvc pipe so it sprays right but as soon as it retracts, the next time the system is on it automatically twists back to spraying crooked! How do I fix this?