The beauty of Blockchain is that it is no use spending the day arguing when transactions like this one from the link below, 100% perfect and registered at Blockchain are not credited to their owners' accounts.
If a perfect transaction registered with proof like this below is not credited there is someone cheating. What should be 100% secure with registration becomes a lottery in reverse, of which a certain percentage of users are drawn to lose their money and the name of that is scam.