Glacier Construction and Irrigation

I hired Glacier Construction to perform plowing. After a communication issue, I asked that they stop their services. This was acknowledged, in writing, by the owner of the company. I asked for an invoice to be sent to me so that I could pay for the plowing they had completed. After asking twice, over a month later, I was sent an invoice for plowing AFTER I had asked they no longer plow for me- which again, the owner acknowledged. The owner is now refusing to correct the invoice and send me a proper invoice with the plows I approved.l stating that I can just “pay what I want” of the invoice. Given they charge a late fee on unpaid balances, I don’t think it is incorrect of me to receive a proper invoice with the proper amount that was approved by both parties. The fact that this company charged me for plowing after I fired them is insane and I am not sure why a business would do this!