I found that if you break the portal when you enter it,it will send you to a world have no block,mod,sun,and moon.
In this world,all command can't use,like/kill,/tp,/gamemode.
I not make up a story or kidding.
You can fix it when you quit the game and rejoin.
sometime you have try a few more times.
I tried multiple times but was unable to reproduce this. Could you please attach a short video of you reproducing the issue? If the file size is too large, you can upload it somewhere else and link to it here.