Airline placing negative marks against your name

Has anyone experienced something similar? In October 2017, I was flying Cathay Dragon from Chengdu to Hong Kong and when I checked in there was the realization that I had a couple of those charging power packs (which I understand have lithium batteries) in my checked bag. The bags never went through. I removed the items before the bags went past the check-in desk. Since then every single time I have flown Cathay Pacific and/or Cathay Dragon I have been detained/delayed at check-in. We are talking multiple times - from Chicago, from Singapore, from Hong Kong, from Shanghai, from Chengdu and on. Even when I connected in Singapore getting off a Qantas flight from London and taking CX to HKG, I was detained for 20 minutes when I handed over my boarding pass. The airline has confirmed that is the reason and refuse to do anything about it. They have put a black mark on my name and keep using the excuse of security. Two CX reps at check-ins have eventually over-ridden the message realizing how silly this issue is. Not one other airline has stopped me eg: during a one week period in September I flew British, Finnair x2, Vueling and American (hate admitting that one :) ) there were no such issues, but a week after with CX at ORD it happened again. I have been back and forth with CX. Anyone know how long something like this can go for and what can be done (besides using another airline)? Thanks.

Why the negative "thumbs down" on CrossCourt's post?

Yes, I've heard of this and it's indeed possible. Especially when there's a FFN attached to the booking.

I'd escalate through to the CEO's office - a letter, on letter-head telling them you've learnt your lesson and are remorseful. Just "own" the original issue - regardless of whether you removed the bags or not. Remorse goes a long way.

If you removed the batteries before you reached the check in desk how was Cathay aware of it?