My nether portal suffocates me. On my friend’s

On my friend’s realm, when I’m in the loading screen for leaving the nether I begin taking damage but as soon as it goes away I stop taking damage. It only happens when I leave the nether, never when I go to it.

On my friend’s realm, when I’m in the loading screen for leaving the nether I begin taking damage but as soon as it goes away I stop taking damage. It only happens when I leave the nether, never when I go to it.