If the tile has cracks or chips, then there is nothing to be done and damaged tiles must be replaced with a new. It is not for nothing that experienced craftsmen advise to leave 5-10 tiles in the reserve of primary styling-you never know what! If there are no tiles left in the reserve-you need to choose the same in color and shade (which is not so and just do) or turn on creative thinking and invent some kind of pattern of tiles if you could not choose the necessary shade. In the latter case, you will also have to remove several “healthy” tiles to create a semblance of an artistic solution of laying tiles.