There is an error when I want to remplace a world in Minecraft Realms for Nintendo Swich

When I replace a world on my Realm server it tells me that an error has been made. I can't do anything, I have tried everything, I have even looked on the internet for error pages describing the same error and I have not found a solution. I want my money back because this is not the 1st time. I already lost € 8 in April 2020 and I don't want to lose it again.