Silicone RTV 4500 Food Contact Safe High Strength Silicone Sealant, Clear (2.8 FL. Ounce)

If you want to be sure, remove all of the old silicone and start over. Try to see where it's leaking and see if you can seal it with a white silicone gasket from the outside. If not, get some food contact silicone (RTV 4500) and use that. Don't assume the guy used the right stuff. https://a.co/d/04pCVPlT