Disappointing service

Good day

I contracted Jeanre Herbst with a building project,I then gave him my mother's house plan for him to work with it right. In August I decided we install alluminium doors front and back, problems kept arising with the doors and I kept calling him for his workers to come sort them out. There is space in between the doors and the door frames where dust and rain comes in and he said should that happen he will come fix it now he doesn't want to after I paid him R18000 for the doors that he probably bought for half the amount at cash build. Please help me to get either my money back or he comes to sort these doors out.