Product: Credit card or prepaid card

I have a Delta SkyMiles American Express card with a limit of {$5000.00}. Recently I've needed to make a lot of purchases. I've dealt with the {$5000.00} limit by making purchases within the limit, then paying off the balance, thus freeing up more credit, and then making additional purchases. At no point have I reached the {$5000.00} limit. All payments, without exception have cleared my checking account. Each and every time I verify my available balance is reflected when I log onto the American Express website before attempting new charges. Today I logged into the site after the latest round of payments cleared my checking account and confirmed my available credit. I then attempted to use my card for another purchase but was declined, despite having more than enough availble credit. I called American Express and ultimately talked to 4 different representatives. 3 customer account representatives claimed that I  had " overused '' my account. When I asked them to explain, they said that I was over my limit. I then confirmed again by logging into both my checking account ( again verifying all payments had cleared XXXX and American Express ' own site to again confirm my available credit. The 3 reps then said that it was a policy that a cardholder such as myself can not, even with payments being made so I never end up going over the limit, spend more than my total credit limit within a billing cycle. I then made the point this doesn't make any sense, seeing that I had spent over {$12000.00} in the past 2 weeks alone. I then asked to be shown a policy that reflects this rule. It was here where I was transferred between the 3 customer service reps and a rep specializing in terms and conditions. The rep with terms and  conditions said that there was no such policy and transferred me back and forth between the aforementioned customer service reps. By the time I got to the 3rd customer service rep who told me the same thing, but could not answer 1. Why if I'm supposed to be limited to {$5000.00} during a monthly billing cycle have I been able to spend over {$12000.00} in the past 2 weeks alone? 2. Where is this policy they are referring to in the terms and conditions? And 3. If the specialist in terms and conditions says there is no such policy, why are 3 different reps giving me a bogus explanation of a policy that doesn't exist?

Lastly, when I asked to speak to a manager after having this conversation with 3 different reps, I was told a manager wasn't available, but would call me back some other time. I offered to hold to wait for a manager to contact me but was told no managers were available at the time. 

On so many levels this is completely unacceptable. Terms and conditions should always be clearly available to be produced to any customer at any time. Terms and conditions should make sense, be easy to follow, and be consistently applied. Internally between departments and representatives those conditions should be followed. And lastly, when those reps are in conflict with one another, a manager of a giant multi-national corporation should be available to fix the issue quickly and very transparently. American Express has completely failed in all of its responsibilities here and I am extremely unhappy about it. I most certainly want my issues dealt with immediately, but I also want the systemic faults put on glaring display by my experience addressed so that the next client in my position is not put through the process I've been put through. If this is a routine problem the CFPB has had reported to them, then clearly American Express is guilty of violations in how they treat their customers and should be fined a substantial sum so that are penalized for their conduct, and forced to make amends for their practices. 

Sincerely, XXXX.