Leaking toilet

Swanlander

There has been a slight leak on my toilet where the bowl meets the floor. I have a maintenance contract with British Gas / Dynorod and a plumber called two weeks ago to fix it. He said the flexi pipe behind the boxed in toilet had a crack in it and he replaced it. All fine until yesterday when I noticed a small amount of water , again at the front of the toilet where it meets the floor. So Dynorod came back and he replaced the pipe again and also put a new sealing unit of some sort on to replace the old one which he said was fine but he was looking for solutions.
He then flushed the toilet several times and then went. Two hours on and there is a small amount of water (not much) again where the toilet bowl meets the floor and at the front as always.
I am wondering if there is a hairline crack in the toilet bowl. Any thoughts?