it's not only me who experienced what I've experienced, last week I bought 500 one card recharge card, I've try to load the card but it keep telling me pin is incorrect, I try to recharge with Airtel but it keep telling me pin is incorrect I log to Facebook message their Facebook page, at the end of the day they tell me the card has been used by another customer they even show me a number that the card was load through, I know that I scratch the card myself, I even call the number but is not going through.
I thought this onecard is going to be helpful to the masses, but they let many people I know down, they lose my believe with them.
my advice here is that we should at least go away from onecard.
below is a reference of my chat with them.

You people sef, any small issue Na scam.

Please don't say they are scam as regards your experience as the response might be correct, or you think dubious people or agents cannot use thecard and put that seal again, what cannot happen in Nigeria.

khalhokage:
You people sef, any small issue Na scam.

experienced this for more than 3 times

mcheeew

Eiyaa fa, sorry for the inconveniences

Which one is onecard again, abi na outside Naija matter?

Onecard ko Onecorner ni

Dollarship:
Onecard ko Onecorner ni

I always recharge with one card. Though there are issues sometimes but it has even greatly reduced. It always save me the stress of looking for card for different networks.