I agree. I've always clipped 1 wing only. And as soon as I saw one was starting to fly again, I knew it was time for a chicken round up & they all got clipped again.did you clip both wings? It is often more effective to clip just one wing on each bird rather than both. Clipping both wings can sometimes leave the bird able to overcome the missing feathers enough for some flight, clipping one wing can serve to throw the bird off balance and prevent such flight.
This maybe a good optionDepending on the amount of fence we're talking about, another option is to install a topper that comes in at 45 degree angle and is a foot or more in size -- the reason this can work is that chickens tend to walk clear up to the barrier (fence) and then try to get over it. Because of this they will rise up at the fence line and end up impacting the angled barrier at the top rather than going over the fence. It can be done with bird netting, poultry netting or other wire/mesh style materiel.