It was one of the tools that allowed me to maintain healthy credit card usage habits. In my idle time when messing around on my phone I’d gotten into the habit of just transferring money from my checking account to my credit card, often in excess of my actual balance, so as to cover “pending” purchases.
Not only will my bank no longer let me do that, just to twist the knife a bit, they will let me make multiple payments totaling the pending total due so long as no individual payment exceeds my actual balance.
So it’s not that they can no longer handle negative balances on the card, it’s just that they’ve half-ass made the interface disallow it.
Nobody said anything about OP doing it wrong, cool your jets. The bank changed their policy. At that point your options are either take the advice of the parent comment, complain to the bank (which will likely get you nowhere), or find a new bank. Don’t get bitchy at people offering advice.