I couldn’t find any model to open (??) in your read-only link, maybe i just missed it?
In any case, you probably need to re-check your click triggers, maybe you missed a small detail, because usually when models open once but then don’t work again it’s because the triggers are not set correctly.
Remember, modals, or pop ups, need to be opened and closed, but when they close they need to be “reset” so that they work again when you try to open them again.
EDIT: Also, i compared your triggers to the ones i have on a project of mine, and i think you got your close animations backwards:
On close modal, you have the following → HIDE/SHOW (display:none) and then OPACITY (0)
What you should have → OPACITY (0) and then HIDE/SHOW (display:none)
EDIT 2: You can also have a trigger (on page load) that resets your modal, opacity (0) and hide/show (display:none) and set these attributes to “set as initial state”.