Did Not Stick to Initial Agreement.

The owner of this business is ************* and unreliable. I found him for the company that I work for to do an aluminium glass door for our new offices. We had a verbal and written agreement that he failed to stick to. He required a 50% deposit so he could get materials which he did and delivered but he did not get material worth the money we paid him. The initial agreement was that he was going to start work on Friday, 26th of April and he texted me Thursday afternoon that he was still working at another place and would come Monday. When we were talking throughout the week, he assured me he would start on Friday and I let him know that this was an emergency. Because he did not stick to his agreement we required him to pay back the remaining deposit so we could get others to replace him and he also agreed. However, till today, Mpumi keeps lying and telling us that he will pay the money and doesn't. Since Friday, 26th of April he has promised to reimburse us what is due to us but he does not he just keeps on lying. He is not an honest person, he is ************* and unreliable as a person and as a business because this is unprofessional.