Complaint sub-issue: Problem during payment process

On XX/XX/XXXX, I purchased XXXX money orders at a local merchant, issued through XXXX XXXX, for {$500.00} each for a total of {$1000.00} to send as a payment to an active credit card account with Citibank. I sent them to the payment address for an Ohio Citibank office listed on the official Citibank website. I continued to monitor my account during the two weeks that followed and noticed that my payment of {$1000.00} had not been posted to my account and applied toward my total balance. I called Citibank Customer Service on XX/XX/XXXX, to address my concern. After a period of searching with no results, I was told by the Citibank representative that a payment investigation would be opened for my account and that my account would receive a conditional credit while the matter was being looked into. I informed the representative that I sent the payment to the Ohio payment address that was listed on the Citibank website. She proceeded to inform me that the Ohio address was no longer valid and that they have since moved from that location. She said to wait 2-3 days to see if my payment of {$1000.00} would be forwarded to the current location and that she would sent information to me that required me to send a copy of my money order receipts as proof of payment. I waited but nothing was posted to my account. I immediately sent a copy of my money order receipts to Citibank in the envelope provided in the letter sent to me about the payment investigation on XX/XX/XXXX. I called the Customer Service number listed on XXXX XXXX money orders to inquire about the XXXX money orders I had previously purchased for {$500.00} each. The XXXX XXXX automated system had informed me that both of my money orders that were sent to Citibank had been cashed on XX/XX/XXXX. I then contacted someone with Citibank through the online chat option on their website. I was told that an investigation was being conducted and that if " they needed information from me, that I would be contacted ''. I was never contacted by Citibank and proceeded to wait for my {$1000.00} payment to post to my account since I had knowledge of the XXXX money orders being cashed. I called Citibank on XX/XX/XXXX, and requested that a supervisor reach out to me. I was told that a request was put in and that a supervisor would call me within 24 hours. No one called to address my concern. I then called onXX/XX/XXXX, to express my frustration and to inform them that I was never contacted by a supervisor. The supervisor that I spoke with seemingly made it out to be a mistake that I had made with my handwriting or that " sometimes these things happen ''. I refuse to believe that someone could misplace {$1000.00} when I have sent multiple payments of {$90.00} which have been applied to my account without issue. I received a call approximately two hours after reaching out to Citibank by a separate supervisor. I remained on hold for almost an hour while she made several attempts to locate my missing money orders through account information and by requesting the specific money order tracking numbers. After searching with no results, she apologized and offered a {$50.00} credit to my account to attempt to compensate for my wait time and the inconvenience this entire process has caused. She also informed me that they still had not received the information I had mailed in as proof of payment and requested that I send it again, only this time to fax it to their payment investigations office. I mailed a request for a photo copy of each money order from XXXX XXXX that cost me {$15.00} each and am currently waiting for a response from XXXX XXXX so that I can then send this information to Citibank. I received a letter from Citibank today stating that they reversed the conditional credit of {$500.00} that was applied to my account previously and that if I can not provide a photo copy of the original money orders totaling {$1000.00} that there was nothing further they could do. These money orders were written to Citibank and were cashed by someone with Citibank. No one has given me an answer as to why my payment of {$1000.00} has not posted to my account or where it may be. The information I have as of right now is that XXXX XXXX said that the money orders were both cashed and that a supervisor from Citibank said that " sometimes these things happen ''. You do n't just lose {$1000.00}.