Downloading world to realm

When I try replace a world with a current world I already have on a realm, it shows up with an error.
I know this has been an ongoing issue since 2021 as there has been youtube videos to 'fix' this issue from that time, however, none of them worked.

I am aware that the size of the world is over 200mb so I tried it with a world that is 1.37mb however, that did not work either.