Does not warranty work

I had $2200.00 of work done at mr transmission in sugar hill, ga., work included rebuilding the transmission on a 2001 mercury sable, complete break job; both front and rear, with replacement of front rotors. Recently, I developed bad break pulsation and took the car back with less than 10k miles of wear. Mark/current mgr said under new ownership and do not do breaks and can't do anything for me. Its funny, after I took the car back when the transmission was not quite right, they gave me a rough time before they fix it. In less than 6-months, the place has change ownership twice and new owners will not warranty previous owners work. I learned my lesson.