You can die while building terrain in a portal

Whenever you go into a portal, it will of course switch to generating terrain once you have been in the programmed amount of time. However, you are still killable while in the building terrain stage. I was full health with no mobs nearby in the nether, wearing half gold armor. It was building terrain, and I had almost finished, but then suddenly boom. You died. Hoglin standing their when it wasn’t before. I was full health. I lost 26 xp levels. I was very upset, because this is a no cheats world with no mob farm yet. It’s really hard for me to get levels, and I was saving up for enchants. Please fix this glitch, it is infuriating.