Often clients come to me who have been scammed out of their bitcoin assets and then scammed a second time, as most recovery companies are also scams. How do you recognize a recovery service that is scamming? Mostly by the too good promises. Who says without knowing the details that he can recover almost all Bitcoin, has no idea or is a scammer. If the fraudster, for example, has not yet moved the captured Bitcoin, then you can usually do nothing yet and must be patient. Then it is not yet worth paying for a service. Furthermore, even after the perpetrator has been found, the home countries of the perpetrator and victim may not provide any legal support to each other. This shows that promises to get everything back are nonsense. But in many cases it is possible to find the perpetrators, because it is difficult not to make a mistake. And once something is written in the blockchain, you can't undo it. Besides my own service, I can recommend forensicsone. There are also other reputable services, but please be careful, there are by far more bad ones.
Good luck to all who got their bitcoin stolen!