Spirit Airlines Refusal to credit legitimately-earned miles to frequent flyer account Miramar, Florida

I telephoned Spirit Airlines when I noted that they failed to credit me for the miles I accumulated for a recent flight to Detroit. The representative (in India) with whom I spoke was unsympathetic and defensive when I inquired as to why the miles did not appear on my account. He impatiently stated that I did not request the credit early enough, and that they would, therefore, not credit me the miles flown. This flight was taken about 5 weeks ago (not 5 years ago)! Spirit Airlines knows very well that I flew on this flight; they have the confirmation number. Interesting,and slick maneuver on their part, but horrific public relations. For the 1250 miles they saved by denying the credit to my frequent flyer account, they lost a customer!