C-4 VENTURES INC

I took my 2 vehicles for an oil change and they put a blend oil for 2 of them. It was more expensive than the basic oil. So they charged me more than regular price saying that this oil last 5000 miles or 5 months. And I changed the oil and left. And I came to same store after 5 months later to make an other oil change. And they I was told that the oil they put lasts 3 months only. And I explained them what I was told at that time and they told me that that certain branch was running by other people at that time and they were doing last of wrong stuff and they are receiving lots of other complaints. Basically thy said there nothing to do with them they are the new management and they are not responsible for their fault. After that I've called their corporate office to address my concern and a lady she received them But never got back to me after couple month. I've called her so many time left voice mail but no luck. Now My car doe not wok as smooth as before and making noises.