My phone has more than enough space available, this is not the same error as when phone space is an issue. 

I've been paying for a realm for months now, and recently I've been unable to download the world due to a size limit that I was NOT made aware of before signing up for this service.  It's untenable to continue playing on this realm indefinitely as I'd intended if I won't be able to download it at regular intervals. 

I see similar issues posted here, but they're being grouped into the "your device doesn't have enough space" bug, which is not this. Please understand that this is an issue which, if not resolved, makes long-term realm subscription worthless.