Don't buy parts that they recommend

Service technician arrived for my appointment this morning... and just as I thought, these screws were not the correct ones nor were they needed. I will be contacting you to dispute the non returnable statement since your parts department that I spoke with told me that I needed these. Extremely dissatisfied that after a 1 1/2 hour ordeal just to get an appointment scheduled, your representative told me to purchase parts that weren't necessary.