Cut out the damaged tile with an old wide-bladed chisel, working from the centre outwards. Take care not to lift or damage the edges of adjoining tiles. Use a wide stripping knife to remove old adhesive, then brush away all traces of dust.
Apply new adhesive to the floor with a serrated spreader. Next-having immersed the tile in hot water to make it more pliable and dried it off – bend it slightly and ease it into the corners. Then press it down firmly, working from the centre outwards to remove any air bubbles.