[Tones]

If I am not mistaken, this is a cartridge or cannister type filter with a reusable cap and a replaceable element and o-ring. It is likely that they scratched the cap when changing the o-ring or the cap has distorted. Also possible they are not replacing the o-ring to save time. I would suggest you tell them to examine the cap closely during the next oiil change or even ask to see it yourself. Make sure they are changing the o-ring. The cap is usually not expensive and you may just tell them to replace it for peace of mind.