The original bottom cap broke due to tension from the normal twisting the top spout.
I used TinkerCad to design and replace that bottom (black) piece.
IF you increase it by 05% it will be a looser fit so that it will not keep tension on the piece.
I used this green PLA to test, I had planned to reprint in black nylon for strength but,
will now just reprint in black PLA with no stress on the new bottom piece.
I will update if this PLA fails, so far it has not.