Are you new to being in water?
I can not help you, but on video you sometimes see someone holding their nose when they jump in the water for the first time - maybe it is the same if you are new?
It will pass I am sure, as I don't know anyone having this issue...
I am in the water a lot, hydrofoiling, dragging often to get back to my board.
So if noone has the "secret" to avoid it now when new, don't worry it will pass and be non existing later