Product: Credit card or prepaid card

XX/XX/XXXX I applied for and was approved for an American Express SPG Business credit card. The card came with a welcome offer for XXXX points if you spend {$3000.00} within 3 months. I spent the required amount within the time-frame allotted and waited for the points to be applied to my account. After several weeks I noticed that I had not received the welcome points. I reached out to American Express via their chat on XX/XX/XXXX to find out how long it would take to deposit the points. It was at that time I was informed that I had not met the requirements of the offer. When I asked how was this possible the agent told me that I had not spent the required {$5000.00} needed to receive the XXXX points. When I informed the agent that was not the offer I signed up for he said it was and said that's what I agreed to. I asked to speak to a manager and was given a supervisor who told me the same. I continued to try and explain that was the wrong offer assigned to me but the supervisor said there was nothing they could do. After continuing to press the supervisor finally said they could open an investigation but it would be several weeks for a decision. I agreed and waited for communication on the investigation. On XX/XX/XXXX I reached out to American Express again via chat because I had not heard anything. After recounting the issue all over again and adding that no one contacted me about the investigation I was informed that the investigation was closed and the offer attached to my account was for $ XXXX not $ XXXX. I asked why was I not notified and was told by the supervisor that there was nothing they could do. The same day I then called the American Express customer service number to speak to someone directly. I spoke with a supervisor who told me the exact same thing as the chat agents. I told the supervisor that I am looking at the American Express website and the offer I applied for is still showing on the site. The supervisor says she looked at the offer and it started in XXXX after I applied. No one in American Express customer service was able to help me or investigate further than saying they don't see that offer on my account. No one was willing to acknowledge there could have been a technical or human error that applied the incorrect offer. XXXX points is less than XXXX points. Why would I make up or lie about getting LESS points?? I specifically chose this particular because the spend was only {$3000.00} compared to other card offers I reviewed. Why is no one willing to take me seriously? I have a XXXX XXXX and XXXX personal American Express credit card. I wanted to stay loyal to American Express which is another reason I chose to open my business card with them. I have been a loyal XXXX/XXXX   customer for years. I am Platinum Premier Elite with XXXX, I have XXXX and XXXX personal credit cards.I am extremely upset and in disbelief that I have fallen victim to the bait and switch scam. I am upset that no one is willing to help and that everyone I've spoken to has treated me like I'm disillusion and making up what I know I read and applied for. I'm upset because I'm a small fish in a big pond and while this is a big deal to me the company doesn't care enough about my small business to try and help rectify the issue.