Auto Magic Not Doing the Magic

My car insurance allocated this dealer for me to fix my car, which had to be replaced with a new pumber and lights that were ******. When i give in the car im told it will take 3weeks to be worked of which it never made sense but i was cool with that. On the due date when the car is supposed to be released , i call for update , I'm then told the insurance has not approved the additional amount as the quote initially submitted was not correct. Here they quoted wrong lights and i dont how because they had the VIN number. I then call insurance to find out what’s happening, insurance tells me they were doing investigation as it doesn’t make sense for them to be quoted incorrectly however they decide to pay the additional. Now the dealer extends with another week only to find out on the new collection date , they say their supplier gave them headlamps that are not in a good shape. I started wondering if they are using black market or what. Its a fifth week now , i don’t what they are doing to my car that is taking 5weeks, all i asked for was a replacement of my bumper and lights. The service and level of incompetence I'm receiving her is disgusting.Please review the dealers allocated by insurance before taking your car there. This is just ridiculous.