I, German, once saw a mail-crime being done as the co-owner of a UPS associated package handling business. Some scammer had sent mail to people and they were sending back - to a post box we managed (we had not know what it would be for when it was ordered) - actual money. We called the police - and they said it wasn't their responsibility. Everything was done voluntarily after all. I called a well-known organization - they do just shrugged and told us to just go ahead, nobody would and could do anything. Pretty much that if people were so stupid to fall for it and sent money vial mail to unknown people, quite voluntarily even if scammed, they could not do anything. The scammers used a Delaware company and a Canadian address and they were sending their scam mail (actual mail) to Germans. Probably bought some address list somewhere. No chance to find them, but even preventing the ongoing scam was nobody's priority.

Also, I once returned a wallet thick with various cards, all paper money already stolen but things like drivers license and other important documents still inside. I brought it to the police. I waited for almost an hour in line, and then it took more than another hour of the officer documenting every single item in the thick wallet. He had to, he could not just write "wallet", it had to be every single item.

I highly doubt the police will do anything. Scams don't seem to be anything the police will go after, maybe some very high level stuff when it's about millions. They are also very busy writing reports and doing other important paperwork... /s Googling I just found that there are 760 cases of bike theft per day in Germany. Less than a tenth of them are found. -- https://blog.alh.de/taeglich-werden-ueber-760-fahrraeder-ges... -- There is just too much "small stuff" for police. If anyone gets murdered I just have to wait a day or two for the newspapers to announce the murderer has been found. On the other hand, for small crimes I expect not much is going to happen apart from filing the report (which I'm sure alone takes up plenty of time).