Complaint sub-issue: Can't use card to make purchases

I applied for, was approved, and received a Citi Diamond Preferred MasterCard with a {$6300.00} credit limit and 0 % interest for 21 months on purchases & balance transfers. I submitted the application and received approval on XX/XX/XXXX. However, getting there was a challenge because I have a credit freeze in place at all 3 agencies ( just for general security & for 10 years ) and Citi refused to tell me which agency they would use. So, I had to lift the freeze for all 3 agencies, which caused considerable delay, hassle, and cost me {$10.00} because I was missing one of  the PIN numbers. All unnecessary because that was not the agency they used. 

The reason I acquired this card in the first place was to make several major purchases and then, hopefully, pay down the balance prior to expiration of the no interest period. One of those items was a camera and I found a great deal ( for {$1700.00} ) on my chosen model prior to getting the card so I put it on another card. I then decided to use my new Citibank card exclusively for all smaller purchases until they totaled {$1700.00}. Which I began to do. 

Another item I wanted to purchase were components to build a new desktop PC. I had an email with a one-day sale at XXXX including several of the items I wanted. I spent several hours putting together an order and tried to pay with my Citibank card. That was XX/XX/XXXX. 

Thats when the nightmare started. After I entered the credit card info, I was given a weird message that I was being directed to my cards website for some kind of verification. Ive been using credit cards for decades and shopping online for a very long time and have never seen anything like that before. I entered the requested information and was sent back to XXXX. I saw an order confirmation email and didnt think any more of it. But after a little while I notice several emails including one that my card had been declined with link to re-enter credit card information. I tried again but my Citibank card was declined again. 

I then signed on to my online Citi account and saw a warning about possible fraud and there was a number to call. So I did. But I didnt get through and then called the number on the back of the card. But I used my home phone instead of my cell ( I used my cell # when I set up my account ). Im not sure if using my home phone was a problem. If it was a problem Citi should have ended the call with instructions to call back using the number I had used to open the account. Or end the call and then Citi call me back on the number on my account. Citi has never called, ever. Other credit cards call me if there is something suspicious and the situation is quickly resolved. Just like the XXXX XXXX ad on TV. I have since added my home phone number to my account. 

The phone call was ridiculous. No issues with the rep. She was doing the best she could with lousy Citi procedures. She wanted to know about other credit cards & bank accounts I had. Apparently, she needed to contact another bank for reasons I do not understand. But every bank was the same story : Im sorry sir, we do have an agreement with that bank. They created a security risk for me by requesting that information. Any information they are entitled to is on my credit report, which they got when I applied. 

We made no progress and I was told I would have to wait for a letter with a form to complete & send back. Its clear to me that this is all about protecting Citibank. The risk from fraud is theirs, not mine. But they have never explained what the fraud was XXXX I doubt there was any ). I didnt want waste all the time ( and sale prices ) I had put into my order for Newegg so I put the order on another ( interest bearing ) credit card. 

Again, that was XXXX. I was able to use my card earlier that day but it has been frozen since. But was only able to charge about {$760.00} before my card was frozen. 

The next day ( XXXX ) I called back, this time on my cell phone ( the number associated with my account ). But no luck. I still have to wait for the letter. But at one point the rep asked for my password. I cant believe I was so stupid to give out my password over the phone. Citi created a security risk for me. No other card or bank has ever asked for a password. Giving them my password proved it was really me but I still had to wait for the letter. I have since changed my password. 

The letter arrived on XXXX with IRS form XXXX. It said something about changing my SSN. I was stunned. I certainly never asked to change my SSN. I didnt know you could do that. I called immediately. Sorry for the confusion, just fill it out & send it back and you can FAX it to this #. So, I did that day XX/XX/XXXX, and sent it via USPS the next day. But I've had no response since. No phone call, no letter, no explanation, nothing. They don't need my SSN. They got it when I applied. 

Next, I sent them a detailed letter, dated XXXX, containing much of the above paragraphs and more. I sent it certified with delivery confirmation and received the confirmation. I gave them 10 days to respond, but, again, no phone call, no letter, no explanation, nothing. My credit card is still unusable as of today, XX/XX/XXXX. I know it's been a while so I guess I'm guilty of being too patient. 

I have excellent credit. Citi sent me an email inviting me to check my FICO score. XXXX out of XXXX. My insurance credit score is XXXX. I recently applied for an auto loan and my credit score was XXXX. 

They have caused me unbelievable irritation and aggravation. Ive lay awake at night so aggravated by all of this. In this day & age of tough competition and intense customer service, Citi has failed me severely. Theyve wasted my time. Theyve created a security risk for me. And theyve cost me {$10.00} plus more in the future because charges that would have gone on my Citibank card will now incur interest charges. Call me stupid but I've made additional purchases in the sincere belief that Citi will make this right.