Finally I got my key and it works!! 

Hi
2 days ago I purchased a win 10 oem key from bit-keys.com using this link
https://www.bit-keys.com/en/details/windows-10-professional-oem-coa
I payed and waited and waited and waited... but no key is send to me.
I sent emails to their contact info email but still no answers.. as the site says "1 min delivery" I think many minutes have passed and many more will pass without any key
I hope this is a mistake