The Chase/Harris Septic

This contractor has invoiced me for services they have not provided.
My house is located below the street level. Therefore, the house is provided with a septic collection tank and a pump system to permit sewage to be pumped up to the town sewage system at the street level. The alarm on the pump controller went off on the evening of 6/13/17. My wife *** contacted the CHASE/Harris Corp. on 6/14/17. Their technician came to the house on 6/16/17, he looked at the system but reported he could not fix anything because he had no tools with him.
The CHASE/Harris technician returned to the house on the morning of 6/19/17. I was at home. He indicated the floats in the septic tank needed some adjustment. He indicated he would use a piece of wire (with a hook at the end) to adjust the floats. He also indicated it wouldn't be necessary to replace the floats. He added that he was happy because replacing any of the floats would force him to enter the tank and doing so would require him to take additional safety measures. After the quick fix conducted by the CHASE/Harris technician, the system operated normally for only a couple of days. The alarm went off again on the evening of 6/21/17. I called them on 6/22/17 and asked them to return to the house to correct the issue.
The CHASE/Harris scheduling person indicated they would come to the house on 6/23/17. I took the day off from work to wait for their technician on 6/23/17. The technician did not show up. After two more follow-up calls, I decided to call another service company to correct the issue on 6/26/17. I called Kats Pump Service around 8:00 AM. They came to the house at 11:00 AM and were done correcting the issue by 1:00 PM. They were paid with a check as soon as the service was completed. The pump system has been operating normally since then.
I called the CHASE/Harris Corp. on the same day to inform them they didn't need to come to the house anymore. I told them they were extremely unprofessional and I had to find another service company to complete the work (i.e. fix the tank/pump system issue at my house). They were never able to complete this job even after I provided them with multiple chances to rectify the issue. As a result, I indicated to them I wouldn't expect to receive an invoice from them.
Two months later I received an invoice for $530 from CHASE/Harris Corp. In this invoice, CHASE/Harris claims they replaced a float in my septic tank. They didn't this work. For this reason alone, I consider this invoice fraudulent. Furthermore, as previously indicated they never completed the work they were supposed to and they did not respond to my multiple requests for them to return to the house to rectify the situation.