Nupco Projects Bad workmanship and service

This company is like a ****. They do really shoddy work, then when one reaches out to have it fixed, they deny any responsibility and you get blocked on whatsapp. We used their services to put in a pool together with paving. The salesperson- Muhammad- is very forcefull (1st red flag) and the job took longer that communicated (2nd red flag). Barely a year after completing the work- which comes with a 36 month warranty - the spaces between the tiles are cracking and (more worryingly) the tiles by the pool are rising up. I sought the views of a different builder, who indicated it's poor workmanship and looks as though the incorrect cement mix was used. I called the company and Mr. Muhammad said it's not his fault, but caused by the railway line close by (bear in mind many neighbors also have swimming pools in same street and no issues). The pool pump was also not properly re-installed. He also refused to provide an invoice upon completion of the work (presumably to hide the fact thay not everything was completed). Again, the company refused to fix it. I had to get a different service provider to fix that at my own expense. Attempts to reach out to *** from the company amounted to nothing. He even blocked us on his phone and Facebook pages. I am currently exploring legal options. *DON'T USE NUPCO PROJECTS*