Ask HN: Have I found a bug in the debit card network?

2 points by gushogg-blake 223 days ago | 9 comments

Background: I'm in the UK, my orthodontist is in the US. I pay them $385/month which they take via debit card.

Three times now (2 in May and once yesterday) they have tried to take the $385 from my current (checking) account and it has failed.

Each time, I have seen a transaction going out to them for the exact balance of my account, down to the penny, leaving me with no money available.

For the ones in May, it took 10 days to resolve and remove the transactions from my account. I can't remember if they disappeared or another transaction credited the money back -- I think they just disappeared.

I've spoken to several support people at my bank about this at length and they've suggested the following explanations:

- coincidence (odds of one in 27 trillion if they were trying random amounts between 0 and £300)

- fraud (doesn't make any sense, I have a good relationship with them and they haven't benefitted anything from these transactions, and I haven't shared my balance with them or seen any suspicious OLB activity)

- a mystery

What's going on here? Assuming my orthodontist's system is requesting $385, how is this translating to a pending (authorised to go out but not accepted yet, I believe) transaction of whatever my current balance is?

None of the support agents I've spoken to has seen this before.

Something to do with currency conversion?

gushogg-blake 220 days ago |

Someone at the bank was finally able to give me a hint: this is a continuous payment authority, which is not the same as multiple one-off card payments.

Someone at the personal finance stackexchange[1] mentioned that with a CPA you "still owe the money" if the transaction fails, which kind of makes sense. Maybe the "transaction for full available balance" was just the easiest way of conveying the notion that "a merchant is entitled to take an amount that's greater than or equal to your full balance".

Still, misrepresenting the merchant's actions with basically a made up transaction seems like a sure way to create confusion where we really need clarity and accuracy.

[1]: https://money.stackexchange.com/questions/168001/continuous-...

gushogg-blake 223 days ago |

More detail: one of the amounts in May was £170.68. The amount yesterday was £24.51.

Also: if the amount requested had been my exact balance, I don't see any reason why it wouldn't have succeeded. I have successfully paid them twice before from this account.

pestatije 223 days ago | |

their requesting $385, but the amounts in your account are £170.68, £24.51...obviously not enough. So this might fall within your banks overdraft facility and how they deal with negative balances.

gushogg-blake 223 days ago | | |

Yeah that would make sense. I don't have any arranged overdraft but my balance can go negative by a small amount in which case it will be displayed. The most likely explanation does seem to be that they are just displaying my balance in a weird way - but still, very odd to show a transaction for a different amount than was requested. And having spoken to them, they see exactly the same thing I do in whatever systems they can access, so it's not just how it's represented to the customer.

jonahbenton 223 days ago |

Your orthodontist is probably using an ass (term of art) specialized medical practice billing system. Not uncommon for smaller practices. Some of these are made by the dude down the block, kind of thing. Total shit. That will be the thing that is issuing the debit. It might be querying for the balance beforehand. The thing to do is find out what ass billing system they are using, might be associated with their ass practice management system, and then talk to those people. It might be stripe under the hood but stripe is not making this mistake.

gushogg-blake 223 days ago | |

That was another possibility I asked about but the bank said it's absolutely not possible to query the balance. Could have been misunderstanding what I meant, I guess, or just wrong - do you know for sure that it is possible?

jonahbenton 223 days ago | | |

Traditionally under ACH I don't believe balance inquiry is available. But if you did a Plaid like thing to "connect" your card, your balance is available to payees.

https://docs.stripe.com/payments/ach-direct-debit/accept-a-p...