Product: Bank account or service

I opened an account with Citi Bank ( representative XXXX ) over the phone, on XXXX/XXXX/16, in response to an advertisement on the Citi Bank website, promising {$500.00} bonus for a new Citi Gold account with {$50000.00} deposit within a month, with promotion code XXXX. I gave the promotion code and made sure that I qualify for the bonus, asking the representative and then the supervisor to confirm that I will get the bonus. I was assured by both that I have to keep {$50000.00} for 30 days and I will get the bonus, but if I withdraw the money earlier than 90 days I have to pay a fee. This was confirmed later multiple times by representatives and supervisors while Citi Bank was trying to transfer the funds from my XXXX account to the new Citi bank account. It took Citi Bank almost a month to do the transfer of funds ( deposited on XXXX/XXXX/2016 ), and multiple calls and conversations with supervisors who assured me that I will not miss the deadline and I will still qualify for the bonus, because the transfer delay is a Citi Bank error. When I did not receive the bonus after 30 days ( as promised by the Citi Bank representatives ), I called again and I have been always assured by the reps that I will receive it, just I have to be patient. Then when I did not receive the bonus after 90 days, a customer service representative submitted a request for an investigation. The investigation concluded that I do not qualify for a bonus, because I opened the wrong account! Opening the wrong account is not my error. This is an error of the Citi Bank employees. Citi Bank can very easily clarify this, because all calls are recorded, and assure themselves that this is an error of their staff, not mine, but they chose not to do it. I do not think I should be penalized for the error of the Citi Bank employees. With no Citi Bank in Vermont, asking for Citi Gold account, giving the right promotion code, making sure that I qualify for the bonus ( asking multiple times the representative and then the supervisor to confirm that I will get the bonus ) is everything I could do when applying over the phone. The role of the customer service reps is to help the customers find the right account not to try to mislead them, especially the elderly. This seems a very elaborate way to attract funds : promise compensation, assure their clients for months that everything is right and then investigate and conclude that this is the wrong account. 
I have never had such a bad experience : false advertisement, terrible customer service, misrepresentation, age discrimination. Opening an account on the phone, I do not have any control on what the representative will do. Moreover, for more than 3 months I have been assured by the Citi bank reps and supervisors multiple times that I will get the bonus and instead of thoroughly investigating the case and the work of their staff they chose to take advantage of old people and penalize them. 
I am wondering whether misrepresentation, false advertisement and age discrimination are part of the official Citi Bank policy or just their reps are very poorly trained and their clients have to suffer the consequences. In both instances it is a very dangerous trend which should be investigated.