Was there no space available in first or was there only economy available for the flight you needed?

I am asking as I went through a rebooking with AA three months ago and the agent only wanted to rebook me in economy despite first seats available.
I don't understand why some agents insist on downloading passengers for no reason if I paid their employer for first class. I had to get two supervisors involved to get what I am entitled to.

As for compensation after the fact you might be entitled to a refund although AS might try and tell you that the fulthY fare is more expensive than what you have.