Urgent Car Repair Assistance Needed

Hey everyone, I bought a used car back in December. A few weeks ago, the transmission went out. I have a warranty on the car, but they're fighting me on covering it. Without my car, I'm stuck. I do not make enough money to pay for two car payments, so my only option is to pay for the transmission myself. I hate to even ask but I don't know what else to do. Thank you.