Product: Checking or savings account

I am a credit card customer with Citi, I continually received a pop up promotion on their website each time I accessed my credit card account. The pop-up was a promotion for customers who have not had a checking account with them to open one up, meet certain criteria within 90 days and receive a promotion of {$300.00} after the criteria was met. I reviewed the promotion requirements that indicated the promo was valid from XX/XX/XXXX to XX/XX/XXXX, must have at least 2 enhanced direct deposits into the account with a combined balance of {$1500.00} for the total of the deposits ( verified that this included XXXX Deposits ), and within 30 days of meeting these requirements the {$300.00} would be deposited in the new account. To open the account there was no promo code, only a link which I followed on my mobile device to open the account on XX/XX/XXXX with the minimum opening deposit of {$25.00}. I received instant communication the account was successfully opened. I proceeded to receive 3 enhanced direct deposits via XXXX totaling more than the required combined amount of {$1500.00}. The XXXX Deposits where on XX/XX/XXXX for {$100.00}, another on XX/XX/XXXX in the amount of {$500.00}, and lastly on XX/XX/XXXX in the amount of {$1000.00}. In XXXX after seeing I still have not received the {$300.00} promotional credit I stopped using the account until I was able to call them and find out why I had not received my credit. On XX/XX/XXXX I see that I start to get charged a monthly service fee of {$5.00}, so I use this opportunity to call Citi on XX/XX/XXXX to inquire on why I have yet to receive my promotional credit, yet there sure have taken the opportunity to charge their service fee. The representative I spoke to had no idea how to help me as he was not aware of how the promos worked so I asked to speak to a manager or supervisor. Once I began to speak with the supervisor she asked me for a promo code for the promotion, I explained to her that there was no promo code instead only a link to open the account of which is still present on their website so she can see that there is no Promo code visible at all or a place to even enter a promo code. She explained to me that she needed a promo code and I tried to repeat that there was and is no promo code instead it's a link on the website that she would be able to see as well, she would not give me a chance to explain this only advising that she was not going to check the website and would not let me speak further before she rudely hung up the call on me. I called back, spoke to another supervisor, explained exactly what had occurred all over again, the associate indicated she could not help because there was a different department that handles the promotions, but they don't speak with clients directly instead they would submit a research request. I was told I may have been granted a promo for a different promo of {$100.00}, however I explained that was not the same Promo I opened the account with, that it was a different promo as I was explaining. The supervisor placed the research request in advising she had no other information to assist with and advised it would take up to 15 days for research and gave me a reference letter. Upon the call ending with the research request supposedly being submitted I instantly received a form letter with the reference letter on it I was provided indicating to me that they are not aware of any such promotion I was to be granted for opening the account. Now although all my communication was via phone and digital options via online channel I was told to further dispute to fax them with no email alternative. In this day in age to require further dispute via Fax is archaic but I faxed them, only to find out they have no way of verifying a fax was received or is even being processed. This company is being unscrupulous, I believe using tactics to prevent consumers from being able to properly receive promotions promised to them and taking advantage of us making the dispute process basically unchallengeable.