Kirk Brothers Chevrolet

I Fredrick Jones had service from kirk brothers chevrolet in grenada, ms i requested online at there website i needed my vehicle repaired for oil leaks transmission leak and motor mount replacement i had my own parts so i looked down the site it stated that they have shuttle service so i requested it for my convenience do to me not having a driver to drive the vehicle nor i had transportation to pick me up from the dealership after i left my 2006 chevy impala ss i had a appointment for 4/10/2017 at 10:30 am so i get a call from kirk brothers tuesday saying that they fixed my problem on my vehicle but my two front wheel hubs or loose do i need them to replace those i was like yes you could ok so wednesday april 12 th i went to the dealership to check on my vehicle i was told they went for a test drive in my impala an now the oil pressure low stop engine sensor comes on an motor starts tapping so i stated my car was not making tapping noises or reading that sensor code when i had it brought here so they told me they would look at it so thursday april 13 i goes back an check my oil it was reading one quart low on the stick so i went inside an guy the service attended came out an checked an said it waa full but i saw different one of the hole on the stick was empty so i went inside paid the amount of 1889.42 an recieved my keys an reciept so thats when i crunk my vehicle an noticed that my engine was tapping an also a loud knocking sound so i cut off the vehicle knowing that my car wasnt having these problems before they did service on the motor so i immediatly tol the service official that my car wasnt drivable an that they had done something to my engine they denied that it was there fault an stated i would have to pay and additional 1800 dollars out my pocket an i told them that it was there fault so now they want refund me half of my money or fix the problem they did to my engine so now im reaching out futher before any futher steps cause i know Gm is a great company an im not trying to destroy the business i just need to be treated fair