Highly unprofessional conduct and after sales services

I called Fabian for a leak at my house. He came promptly the next day to do the work. I asked about his after sales and he said that his work is guaranteed. I was happy to work with him. However after a few days we realised that the leak was not fixed and I called him. He promised to come in two days to check it but it's been around 2 weeks now and when I try to call or message him there is no answer. I thought that he was good based on the reviews here but the way that he is avoiding after sales service is highly questionable