That’s very bad work ! I took my installer to court recently and the court have now instructed a building surveyor...to report to the court. After the process it will take a total of a year fighting a poor installer who claims the works ok...that’s with a gap of up to 16mm of grout and Silicon at the top of the wall which was supposed to be floor to ceiling tiling... I will update people if and when we may win or not. I am asking for a retile. They even tried to send their mate round claiming he’s independent .. to inspect the works, what a joke