Error loading old world into realm

I know that a similar question is already open, but it has been open for about a year, and no solution has appeared. Now I am using the latest version of the game (1.17 bedrock win 10 ed), I also tried it on other devices, but everything is useless, I tried to change the Internet connection, but it did not help.

!!! I can load the new world I just created, however I can’t load my old world, which is only 11 MB !!!

I will upload my world here so that you find out the problem, because when loading into realm, I just get an error, no logs, nothing!