Welcome to the forum!
Yes, leaks and kegs go hand in hand. Many things to consider are new O-rings, lubrication on O-rings and checking for tightness at each connection (post to keg, ball lock to post, threaded QDC to gas line, pressure relief valve and main O-ring in lid). I generally try to spray down each spot with StarSan to detect leaks, but I have a small jar of the Leak Detector on hand for those stubborn leaks that are hard to detect. Also, I turn off my CO2 when the kegs are fully charged and then monitor the pressure maintained in them and any one that loses pressure gets a full breakdown and servicing before it goes back in use. I have one presently that leaks at the PRV and replacing the PRV didn't solve it, so somehow the threads are worn in some way that I will be ordering a new lid to use. First time for that for me, but I don't want to waste CO2 on that leaker!