Been ripped off by a pool company

Very disappointed with the bad service from Thatch Crete. We had a pool made smaller in 2018. A few months down the line in 2019 we realized the fiber glassing was coming loose just under the coping. I reported the issue and was promised it would be fixed. It is now April 2021 and still no repair on the pool. I had an independent pool inspection done at my own cost through the National Spa & Pool Institute and the report detailed what needed to be done to sort out my pool. Yesterday two guys were dropped off at my house and started with the job. When I realized that they were not doing what was outlined in the report I called John to ask why they were not following the procedure as outlined in the report. He was rude and aggressive and told me that unless I allowed the guys to carry on with the work as he had instructed them, he would bill me in future to do the repairs. He had no intention of repairing the pool according to the method set out in the report. So I would be getting a bad job on top of an already bad job. Quite unbelievable.