One more suggestion. When cleaning after firing. when you have it disassembled for cleaning. Run a cleaning rag inside the gas cylinder just like the barrel.
Grit and power residue goes into the gas cylinder to operate the operating arm with each fired round.
Also after reassembling. I never like dry firing a weapon.
As you set the trigger assembly in place. Hold the trigger guard, slowly lower the trigger guard, pull the trigger.
You will release the hammer and not dry fire it.
You will feel the trigger guard attempt to snap down. The hammer spring is exerting force on the trigger guard and hammer. You lower the trigger guard in place and snap it home.