It turns out that even bitcoins coming from an exchange can be flagged as dirty. Yesterday, my wife sent bitcoins from her account on kraken.com to my account on bitpapa.com. My Bitpapa account was blocked, and Bitpapa wrote:
I created this topic a while ago, in which you will find all the discussions related to Risk/AML scoreThese tools are not accurate and give results to the point that they cannot be relied upon as evidence in court and even Chainalysis failed to prove the accuracy of their results when there was an investigation.
The data showed that the volume of illegal transactions:
If the data is correct and compared to trading volumes and there is no unregulated market, the percentage is very low.