There should be a metal track under that molding. The metal track is screwed to the sub floor, in between the tile and the wood floors. The molding snaps down on top of the t molding and should not be glued or nailed.

Thanks for responding. There is no metal track, it has been laid flat and help by nails going towards the wood floor. It is really not a t-molding, it is flat underneath. Sounds like I need to get this "metal track".

You can find what you need at any flooring place. Would imagine big box stores too. Comes in different colors, to match your flooring.