Forever Green Lawn Care Inc

I started with this lawn care service a few years ago. At first, they seemed great. My lawn looked good. After I referred them to a friend, we had another round of fertilizing/weed killing done. The gentleman who did it killed all of my flowers and several parts of my lawn were burned. They also burned up my friend's lawn on the first service. I wrote to the company, they gave me excuses. It happened again, so I withheld payment for several months. They didn't come back. After about 6 months (the start of the next spring) I paid the bill. They immediately came back to my house when I was not home and left a bill for a service they SAID they performed (which was close to impossible considering we were building a new large deck which took up almost our entire backyard with all the lumber and different things. So how was it possible that they fertalized the lawn?? So I wrote a letter to the company, explaining my position again. I DID NOT give them consent to restart my lawn