Paid for work that they said completed but they didn’t

I have spent a fortune here. Payment made upfront promises made delivered selectively. I was told that job was completed for 16 down lighters which was charged and I paid and then I had to get new electricians in due to issues as I couldn’t get hold of them only to find they failed to replace 30 percent of the transformers and took away the parts I paid for to be replaced! They owe me a refund and no one is contacting me they have become completely unavailable.