Product: Credit card or prepaid card

I would like to file a complaint against US BANK for their customer service and credit reporting departments unprofessionalism towards me and their poor handling of my dispute. I contacted the customer service department numerous times last year after my banking and credit card accounts were mysteriously frozen because I was not made aware that a statement was missing and left undisclosed to me. The shocking way in which I found out my credit cards minimum payment was apparently a few days late was by the bank shutting down ALL access to my checking accounts and credit card, which is insane to me because this could have absolutely ruined my life had I been desperately in need of my money. Thankfully I was at the ATM for some petty cash for the day but I was sincerely shocked at how they handled an apparent late credit card statements that was due only a few days before that. No one called me, emailed me or mailed me a statement or a notice of any payment being due or even late. though not passed the grace period. My main reason for this complain is that within days of the missing statement/email reminder phone call I got a notification from my credit monitoring service that I had lost nearly 100 points off of my FICO score because US Bank prematurely sent my monthly status as 30 days late for XXXX of 2018. I had a nearly perfect FICO score before that and have so all of my life. It was XXXX before they affected it.

As soon as I was aware that there was a statement due I called the customer service department and spoke to a representative, made the payment and asked that I be made certain that this would not affect my credit and right on that phone call the representative promised me and assured me that I was still within the grace period and I would not have anything negative reported against name and if by some chance it was I would be able to call in and have them reverse the negative reporting considering I never received any sort of notice for payment due reminder and that this has never happened to me not to mention my excellent customer status with the bank and my mortgage. 
I was furious when I saw my credit report and I went into the branch and spoke to a supervisor who said she couldnt reverse it on her end but if I contacted the customer service rep on the back of my card again they would do it for me. 
I called the department right away and then I was told that I had to submit this dispute in writing. Why? Is that the law, to submit it only in writing? Who is that convenient for? Why must I submit my personal information and situation thru the mail? One letter has completely gone missing and no retuned receipt was sent back to me nor was the letter forwarded back. Who is now at privilege of my birthday, last four of my social security number, complete credit card number and address? Also, this stall method means I look like an unreliable credit customer to all of my other creditors during the extent of their investigation. How is that fair? Why couldnt they take my dispute right then and there? Why inconvenience us and risk the letter getting lost and my credit damaged for even longer and further credit denied to me because of this late payment? Imagine my frustration here. One person leads me to another and no one wants to handle anything that concerns my unique situation. 
Further, I submitted 4 letters, 3 via certified mail with return receipt requested and one via regular mail to ensure that the letters were received by all departments found on the US Bank website ad via XXXX. By the 4th week I only revived back 2 of the certified returned receipts but not from a 3rd department. I dont understand why they did not receive my 3rd letter and I  would like that investigated because I spent a lot of money on these letters and it seems to have gone missing. 
In my letter I specifically stated my issues and my frustrations that no one called me or emailed me or mailed me anything regarding a payment due and I also reminded them of their very own words when they assured me that my credit would not be affected and yet it was. 
I sent this out on XX/XX/ 2018 and in response I received a very generic and unacceptable response from ONLY 1 department in XXXX XXXX, MO. Where were the responses or letter acknowledgment from the other 3 departments? I was disappointed to see that the 1 and only response was generic with no facts or details referenced. Clearly no one read my letter apart from the sentence about the 30 day late XXXX. No one took my situation into consideration and their illegal acts of saying one thing to me and promising me that my financial life would not be jeopardized and them doing the complete opposite is a contradiction. There is not even a single mention of my complaint regarding their poor handling of my credit card account and their dangerous stunt of freezing all of my money and credit pending a payment! 
How are they allowed to hold my financial life hostage until they get a payment? What if I had a life and death situation? What If I had a huge financial decision to make that day? Their action wouldve completely jeopardized me. Why would this company not call me and notify me before doing something like this? 
I have been a loyal customer with them for over 13 years and never expected this kind of treatment. There is some sort of discrimination here for sure because they are illegally ruining peoples lives in order to bank on fees and such. I never received a statement and that is their initial mistake. I sent a huge amount of documentation and it was all ignored and all they want to leave me with is that I can resubmit more information. 

I truly feel that I have been wronged and I would like the CFPB to investigate everything that has conspired here and to hold them accountable for being inconsistent and for such poor customer treatment. My letters were not answered, a response from 1 out of 4 addresses is unacceptable. I was told it was not affecting my credit but it did. My situation was not addressed and a generic shut down of my request to remove the unfair 30 day late on my credit was thrown at me. I have been a loyal customer and being 30 days late is obviously not consistent with me and they have completely disrespected me and over looked that, even for courtesy sake. I do not wish to escalate this to litigation but I have suffered tremendous financial backlash because of the 100 point credit score drop and I have been denied improved interest rate elsewhere as a result. 

( for security reasons I have created an email specifically to monitor and document this complaint and to avoid oversharing online on a public forum )