AutoNation Honda East Las Vegas

I went in and asked to get a diagnostic done on a noise the van was making. I was told it was the alternator and it would cost about $1200. (I recently had the alternator changed from another mechanic. I went on a long trip and back and the van didn’t give me problems) They said the noise was due to the alternator not being an original part. I let them change it out to a Honda original part and they did. It was not until after I paid that I was told a second noise was found. When I get the Van, it had the same exact noise. I tell them about it. I take it back to them. Then they send me a text saying it was the belt tensioner. That they replaced it at no extra cost to me. (My mechanic changed it out and it was still under warranty. I did. It give permission for them to change it) It was never the alternator. It was was the belt tensioner.