Replace world causes realm to crash and becomes unsavable

so basically I and my friends own a realm and whenever something goes wrong we restart the server to a previous copy of our realm and currently, we tried this and it destroyed our realm 

to be more specific we tried the same method download world replace realm we thought it worked but now it crashed and is completely unsalvageable multiple times we tried to replace the realms with no avail to help our situation and currently have to transfer ownership of the realm yet again 

its become extremely infuriating and stressful to know all of your hard work has been destroyed and as of now we have no way to fix it

so I ask any kind developer who sees this and hopefully brings up why and how to fix this issue as I am sure I am not the only one facing this issue