Product: Credit card or prepaid card

Citibank sent me multiple letters and emails, told me that I was pre-selected for XXXX XXXX XXXXXXXX AAdvantage  bonus mile after {$3000.00} purchases. On XX/XX/XXXX, I received this promotion email again, it comes with a non-transferable exclusive invitation number XXXX and an expiration date of XX/XX/XXXX, so I clicked the Apply Now button, and submitted my application on XX/XX/XXXX. 

My application was not approved immediately, but approved on XX/XX/XXXX after the Citi customer rep called me and verified some information, and she congratulated me for XXXX bonus mile at the end of conversation. 

After I received my new Citi AAdvantage card, I called Citi customer service again to check what is the deadline for me to be eligible for this XXXX bonus offer, since I need to make {$3000.00} within the first 3 month, and I was told the deadline is XX/XX/XXXX. 
On XX/XX/XXXX statement, I noticed that I didnt get XXXX bonus miles, even though I have fulfilled all the requirements. So I called the Citi card service, and the customer rep told me that he didnt see the promotion code in my file. I provided him with the invitation number XXXX. 

After a few days, I received a letter from Citi, this time it said I am not eligible for XXXX bonus offer. So I call Citi customer service again, try to figure out why. A gentleman told me that I am not eligible for this offer because they now have new 48 months rule instead of 24 months, and I received the similar XXXX bonus offer 40 months ago ( in XX/XX/XXXX ). I asked him why Citi didnt tell me this 48 month rule when I applied for this Citi AAdvantage card, he laughed at me ( I could tell even over the phone ) and told me that it is in the invitation email, it is my problem for not reading those terms carefully. So I read that invitation email thoroughly at least 2-3 times, finally found that 48 months rule in the middle of grayed fine print area. I asked him several questions : 1. Why XXXX bonus mile was on the top of the screen, with colorful big font size, and this new 48 months rule was put in the middle of nowhere fine print gray area? 
2. Normal rule for new card promotion is 24 months for XXXX XXXX XXXX  XXXX XXXX and XXXX XXXX. Citi didnt let me know their rule is 48 months instead of 24 months, before and during my Citi card application process.

3. A common practice is, if I am not eligible for one promotion offer, I should be notified immediately with warnings like other banks do, before I submitting my application, so I can decide whether I still want to apply for that card. Citi didnt show any warning during my Citi card application process.

4. I believe Citi database should be very powerful, and be able to figure out which client is eligible for this XXXX bonus offer. My question is, if Citi knows I am not eligible for this promotion, then why Citi still repeatedly sent me pre-selected invitation letters and emails, and invited me to apply for this credit card with enlarged XXXX and other my personal info on the top of first page? 

Since the gentlemen was not able to answer my question, he transferred me to his manager. His manager was much nicer. I told her, the most important thing between a bank/credit card company and its client is trust. Today Citi could mislead me on the promotion offer, tomorrow it could fool other customers on the interest rate, or even take away their money, with some hidden terms in fine print. It is definitely not acceptable. She apologized for the misleading invitation email, and offered me with XXXX points, and told me that that is the best she could do for me. I asked her what if I am not satisfied with this offer, she told me that I can file a complaint to CFPB.