Minecraft realms will not replace the world in any way other than resetting it.

I have a realm, and i have tried numerous times to replace it with another world, but it always says either "an error occurred" or "we could not check if your realm loaded properly, try to go in and see". I tried resetting it, and that did work, but I want to replace it. I also tried using the "Play on realm" button and selecting my realm to no avail. I also cannot add any resource or texture packs onto it. Ive heard that I can delete and reinstall minecraft on the app store to fix it, but I do not want to lose all of my worlds. Is there any alternative to this problem?