Send it back again then - you likely need more than just a battery replacement. I would not let it sit as Shearwater will fix it for you, from my experience.Battery was replaced in January. It was fine for a month, but its now worse than it was before.
They pretty much replaced everything but the case on mine and it’s been fine since then. My brother-in-law has his in right now for a similar issue after having the battery fix done last year. The Teric does seem to have some battery issues from what I see here and my own network of friends.