American Express (Never leave home with it)

Found a great deal on a 42" Plasma TV, called AMX to let them know there would be a high purchase made on my card and was told it was not going to happen. Based on my spending for the past six months I could not spend that much. I was appalled and asked why, was told me I do not have unlimited spending, but, preset spending based on my spending habits. Do I need to spend $100,000 plus each month in order to have the freedom I need to use the card as I please. I did the same thing around Christmas and had no problem...What changed? Why change 150.00 each year if I am going to be treated like that. WAY TO GO AMX CUSTOMER SVC.