Lletz Site Not Healing


I had a Lletz procedure done around 15 years ago, fast forward to 4 years ago and I was experiencing bleeding after sex. Tests were done and the result was the site of the original procedure had somehow broken down, it was lasered (took a long time to heal), it was ok for a while but now it's happening again. Anyone have any ideas why the site keeps breaking down and is not healing as it should? My subsequent smears have all been clear (I have them done at the required intervals).

Any ideas?