So in the end in my world I fought withers in the version 1.16 and when I couldn't kill it I used to put it on peaceful because I didn't want to lose my progress. I also had problems with withers where if it reaches stage 2(when you have to kill it with a sword) and the fell in the void. After I updated my game to 1.17 a wither keeps respawning (probably the one I despawned or the one that fell in the void) at an area a little away from my main end island. It spawns again after I kill it or if put it in peaceful (and back in hard mode) and join the game again.
Wesley Lourens
Thank you for your report!
We're tracking this issue in MCPE-62332, so this ticket is being resolved and linked as a duplicate.
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