New bathroom tile problem

[pedro789]

Hi
I’ve just had new bathroom fitted and some of the tiling isn’t up to scratch. I don’t trust the guy who did it to rectify.

If I get new tiler can they fix individual tiles or would the whole thing doing again?

Some of the tiles are visible behind toilet so we’d have to remove it to retile. It’s a nightmare. Appreciate any advice.
Thanks

 

[Dave]

Hi , some pics would help us advise.