I get stuff called oxy from our local pound shop, its supose to go in the washer for stains but I clean everything with it. My hubby allan had a manky old flask that was rotten inside from tea stains. I put a scoop in with boiling water and left it over night. The flask was gleaming next morning and there was no smell. We use it once a month on all our football flasks. Good stuff.
I'd take it back.we had one that made the tea taste funny once..it even had a funny plasticy smell... yuk we just took it back and got a different one.
We had a similar problem with a new kettle with the water tasting so we complained and they sent a new kettle.the water still tasted exactly the same out of the 2nd kettle.I was told that the hard water was reacting to the element inside the kettle.We got fed up so went back to using the old kettle but 3 or 4 weeks later I went back to trying the new kettle and it was normal, so I tried the first kettle they sent me and that was fine to so I now have two new kettles,one for the house and one for the camper.
You just have to keep trying (complain first though )
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