The flow-on damage of billing errors like this can be immense. Ive seen it first hand, and the people working for these companies generally have no idea how much an overdraft fee can ruin someone’s life in the short/medium term.

If the refund isn’t fast enough it also leads to missed rent and bills, all of which have fees for being late, plus possible debt collector issues as most utility companies will send a single missed bill directly to collections these days.

Not to mention inability to buy food, gas/transport to work, etc.