How Can I Contact The Capital One Credit Department?

After filing bankruptcy years ago, there was an outstanding balance on a Capital One Card which I mistakenly thought had been included in my bankruptcy filing. This was eventually sent this to a Collections Agency who tried contacting me at an address I had moved from over 15 years previously! They even served  someone at the address! When I became aware of the outstanding balance I settled it immediately. I have repaired my credit overtime,  however the delinquent payment is now on my credit report. I want to speak to someone in the Credit Department about getting the situation resolved. Thanks in advance, I appreciate all your help. Best Regards.