7Days Locksmith Refuse to issue invoice Houston Texas

They charged me $974 (!!!!) to open my car and rekey it (under distress and with kids in the car in a remote location I did not have any other option, so I had to agree to that number hoping that the insurance company would reimburse me). Then, I asked for an invoice and they gave me receipt that does not include the company name nor address (not a valid invoice) and because of this the insurance company will not do the reimbursement. I have been calling and texting the technician and speaking directly with their office but they won't send me a valid invoice. I wonder if this is because of tax collection reasons.