If na opay you dey use, immediately the transaction fail, e go reserve back to the owner, so hence our two dey do transaction and I tell you say the money never enter my aza, baba I no dey release coin oh, if true true say the transaction fail, make him contact him own bank or try to refresh him balance but from my own end, I no dey release yet. Immediately you release coin, Omo those men no go gree send you funds again. Some vendors are even the ones orchestrating those failed transactions just so you can release coin if your not properly grounded of their activities on P2P, lots of them are just scammers.
You nailed it, it's extremely unwise with the level of information passed here about scammer though one can't be completely excellent in running away or excape scammer but not like this type where the information is almost everyday discussed in the board, falling prey to this kind of thing is lack of knowledge and understand there is no reason to release your holding or coin when you never see successful transaction, there is a saying by my people it's fools that throw away their water expecting that the change of weather can curse a rainfall, in my opinion all you said speak volume in my heart.