Hi, I just got a used refrigerator from a local craigslist ad. The man I bought it from said it was working. I put it in my van to transport it and we laid it on it's side. We knew that it had to sit upright without being plugged in to let the fluids settle back into the compressor and didn't plug it in for over 24 hours. After we plugged it in, it still isn't cooling. Is there something else that could be wrong?