I was making a large purchase at an auction I regularly attend, and sometimes I have to call ahead and let them know I'm going to make a charge. Before I could get someone on the phone, the merchant attempted to run the card, which came back "authorization required". I was told they would need to call me back on my cellphone to verify my identity, which they did. I was told the charge was approved. The merchant received the same message, "authorization required" on their terminal. When I called Diners Club again, I was told to try running the card one more time. When I did, it came back "declined". Another call to Diners Club revealed that my credit report was accessed, and from that information, my credit line was reduced.

Apparently the credit check occurred the same day, perhaps after trying to use the card the first time. Diners Club won't tell me exactly when the credit report was accessed. The information is outdated and all my accounts are current. But until it's corrected by the credit bureau, they won't reinstate my credit line. What's worse, they may reduce it again after my next payment.

Isn't it illegal to tell a customer their charge is approved, then change the line of credit to stop them from making a purchase?