Pathetic workmanship

I bawt my house in 2019 and leon revamped my entire pool for 65k. Since then i havnt recieved an invoice from him despite asking him numerous occasions. 2 weeks ago i noticed my pool had a vertical crack and i called leon to come and have a look at same but he stull hasnt come through. He keeps cutting my calls and ignores my whatsapp messages. When he was doin the pool he informed me that i would have a 10 year guarantee on the marbelite, so nw yhat i have yhis problem he cant keep to his workmanship. From my opinion leon is s rogue and no1 should use him, he is all promises but cant deliver. Oh and also yhe marbelite has full black patches all around yhe floor. Yhat should never happen within 3 years