99 Jeep Cherokee grand laredo won't start

I have a 99 jeep CGL with 100780 miles that won't start. Fuel pump and presssure good, it used to start if you use the key to open doors instead of keyless entry. Now the engine doesn't even try to turn over. Checked battery and terminal and fine checked fuses and keyless codes and according to mechanic they are fine. Now I am at a loss. After the mechanic reconnected the battery it does nothing just sits there. Is there any suggestions anyone can give me the car worked fine until I took it for the last oil change with a new dealership in my area and now this problem started. Any sufggestion for something I can try or take it somewhere and have them look would be great