general problems of the 2005 Chrysler Sebring

My 2005 Chrysler Sebring has a faulty fuel level reading. I have had the vehicle in two different dealerships (the first one diagnosed the problem, but did no service work due to my leaving the state of minnesota; the other two dealerships supposedly did work to the vehicle) first servicing dealership claimed to have replaced the fuel sending unit; however, the problem of inaccurate fuel level is still showing. (what I mean by inaccurance fuel level reading is that the gauge will show one level, but the amount of fuel put in the vehicle is substantially less; much less than a one or 1. 5 gallon reserve would show. ) it is unknown if the original part is available. I have showed the last servicing dealership photographs of the fuel gauge and receipts from fill ups; the last servicing dealership claims there is nothing wrong. I can produce a sworn statement from my wife which will prove my case.