You have a lot of time though, it's just that it gets harder to reverse.
Netflix' fraud detection is garbage and someone created an account with random letters, some throwaway email and my bank account. I didn't notice until it was like three months in. For the two later transactions, I could reverse them immediately and the money was back in my account on the next business day.
The other one was outside of that window, but my bank filed a request with their bank and it took forever, but eventually they paid it back. I believe this works for something like 13 months. Beyond that, you could still sue the person (and their bank) who fraudulently debited money out of your account, but you don't get a default win.
So at least in Germany you have about a year to notice.
Having had to deal with this is a previous job, from what I remember the rules DD are pretty strict and if you mess up as the collection agency, you have to put it right. You also don't get to just recollect - the few times we had software issues, we needed to write to all the people you are going to recollect from and inform them it will happen.
