An article regarding claims that TSA approved keys are being copied and can be used to steal from passengers’ luggage without cutting locks or cutting the luggage.
https://travel.nine.com.au/2019/02/27/10/52/tsa-approved-lock-master-key-padlock
Looks like the TSA needs to issue a new series of approved locks.
Any intelligent low life theif would just buy a set of locks for a few $ to get the small collection of different keys, and go for it. Each lock indicates which key. Once TSA wanted to open one of my cases but their #1 key did not open my #1 lock so they paged me for my key. Nice of them to do that instead of cutting it open. I guess if they cut the TSA lock they would have had to fess up about their ‘skill set and kit’. Maybe that was before they realised they needed a real master?
I won’t waste my time with TSA approved locks. Had a family member who used them and they were cut off sometime before baggage claim at a US airport. The TSA is known to remove such locks and can legally do so.
A simple set of cutters will remove most luggage locks. The lock. Ay be strongish, but the suitcase fittings used with the lock may be weaker.
A lock is also not going to stop undesirables from accessing ones suitcase or stealing things from a suitcase. Locks give a false sense of security and possibly flag that there could be valuables inside.
I have also faced the same problem. The key may be problematic which is the reason this problem is arising. You may sometimes face connection failed with error 651 which can be easily fixed.
If the suitcase has a zip and you don’t attach the lock to one end securely in many cases it can be opened and sealed without unlocking …
That aside - with zero accountability or record keeping, any handler could remove a lock and TSA would neither know there was a lock there in the first place, nor care, nor apologise - probably assuming it was one of their herd who did it, and being above the law, there’s nothing to explain anyway 
A main reason I always use a (TSA) lock is that zips do come open whether by themselves or with help. Doing ‘something’ and having a problem is a better choice than having done nothing and having a problem.
If one’s luggage is compromised and a lock has been cut off or broken it helps your claim. If you had done nothing, check your chances for recompense as they will vary widely, and usually not to your benefit.
Many security measures are ‘feel good’ things rather than true security, but they protect from the lazy perps, a segment that might reflect most of them. eg Why break into a locked house when the one next door has the doors open and obviously nobody home?
Also, many modern luggage items have built-on TSA compliant locks, whether keyed or combination.
