oil leakage, some seal when oil change was to be completed

This is the second time that we have taken this into for routine maintenance and there seems to be again a Oil leak engine area, pan area, when asked about if it was same problem as before was not confirmed but was acknowledged that it was in for a leak before. They want to reschedule to provide a loaner, but I said no, I will just deal without a loaner and I wanted this fixed. This is upsetting, each time I take this vehicle into the shop for routine work, there are more problems. I bought this car because my wife liked it and thought it was a good car and she has wanted a good car for years. This is starting to be a nightmare and this Cadillac is a lemon.