Product: Credit card

Few Months ago we were shopping at the Saks fifth ave store the sales Rep., convince us to open a store credit card to save more money we did open one which is managed by Capital one for me and one for my wife we shopped there few times we got a couple of statements we paid them on time as we usually do sometime after the last received statement we got a letter from Saks Fifth/Capital one reminding us to pay the balance due when we checked our bank website we found out the statement in questions was paid by check number XXXX dated XXXX/XXXX/2016 but the check status still open we called them back stating the check was mailed to them on XXXX/XXXX/2016 by our bank they informed us they have no record of this check and they need to receive payment for the statement we contacted our bank which they contacted Capital one after our bank contacted Capital one they end up by depositing the check and then we thought the issue is taken care of but again we received another letter stating we have a past due account we contacted them again they informed us they never received payment for the account they sent the first letter about we contacted our bank our bank informed us that the check was deposited into Capital one account and provided us with a copy of the check back and front confirming that the check received and deposited into capital one bank account we contacted Saks/ Capital one back they stated they still show the account past due and we still owe a balance they advised us to check with our bank on what we should do we contacted our bank again the bank advised to stop payment on this check and get the money back from them and issue them another check for the balance due to get rid of this problem Capital one did agree on waiving any late fee or finance charge because they know the problem was not from our end we got the money paid back and we paid Capital one the balance due but we were very distributed by this issue as the check was mailed on time with the correct account number written on even though some one crossed out our account number and hand written it again they cashed the check and they deposited into their bank account but they still claiming they did not receive no payment from us so we decided to close both accounts to avoid any future hassle and we though the issue has been taken care of few months later just recently i was applying for a loan and i was informed that my credit score is very low due to someone reporting me paying late for more than 90 days that was a shocking news to me as I do have a very good credit score and I always pay all of my bills on time after I investigate that problem for days I found out that Capital one is reporting me late on a payment they received on time and they cashed the check for it with my account number written on it but they never credited my account plus they kept my check for longer than what they should as the check date is XXXX/XXXX/2016 and it was mailed by my bank not me. today I missed a call from Capital one i spent more than four hours trying to reach the person who called me that was unsuccessful as it seems they are outsourcing their business to XXXX which explain a lot why they kept the check for so long and then deposited it and credited the wrong account for it i was told they can not find me anywhere in their system, as a result of Capital one reporting the wrong information about me my credit score went down to XXXX my loan application is declined which will affect my business badly and this is not fair to me attached you will find a copy of the cashed check back and front and a copy of my credit score. Thank you for your help in this matter