Clear Choice Windows & Doors interview questions

I met with the owners son who now manages the company and is one of the qualifiers as well. There interview went well and I was even asked when I was available to start. I thanked them for the opportunity and requested to be contacted with a start date and salary rate. I received a thanks but no thanks email a few days later. I politely asked why this decision was made with zero response. I understand no one is obligated to elaborate on their decision but after what seemed to be a hire agreement was made, I was very confused.