If I'm reading your other posts correctly - this ticket is part of a multi-leg trip - right? It's not unusual (at least for me) to fly coach in a one class plane as part of a multi-leg "first class" ticket (a lot of service into and out of JAX is on small commuter planes).
When I book these flights - the airline websites clearly show which flights in my itinerary do not have first class seats. You haven't taken the flight yet - so you got the info before you left on your trip. How did you learn about the seating configuration?
Who did you buy the ticket from (most travel agents don't fuss with airline tickets these days)? Robyn