DISGUSTING SMELL FROM GO PURE WATER FILTER

In 2020 I bought a 5 stage Go Pure water purification from Game, and for at least 18 months we had great tasting water. I then decided that it was time to replace the filters and purchased a set of replacement filters and installed them. After around 2 weeks the water started smelling like rotten eggs, I drained cleaned and refilled but the smell was the same. I contacted Tevo via their website bot and eventually I was contacted by a representative from the company who said it must be an overactive top filter and that I needed a proof of purchase to replace (this I did not keep so I bit the bullet and went to game and purchased another).

Needless to say after a week this new filter replacement still smells disgusting and I cannot use the system for fear of poisoning my family. I complained again on their site and to date nobody has even bothered to reply.

My question to Tevo (only humans, not bots) is why is this smell coming from the filter, is it harmful to my health and what is the solution