I have contacted live support and the legal department, and they have admitted their was a error in their database allowing to send promotional emails to problem gamblers, they have let me know they have fixed it after my messages.
It's an honest mistake,Stake.com is not the only one who experienced that I unsubscribed on some of my mailing lists but they keep sending me for the whole month because the database for sending the newsletters has not been updated for those who unsubscribe, if you trust Stake.com you'll let this pass, but if you have an issue besides this one, you can file a complaint but it's going to be a useless complaint.