I found the error while trying to download a newly purchased world. This is something I rarely do, and the first time I try it, ISSUES. I also subscribed to Realms Plus at the same time. Very frustrating. I have over 12Gb's available on the main system and 83GB's on the added SD card. Space is not an issue. To be clear, this is a world by a third-party (Blockception). Those are the ones that I rarely ever buy. I'm thinking a refund is the better option until you get this fixed. Why pay for something that doesn't work? I'll pay you when you fix it.
This is for the Switch. You mentioned Playstation. Wrong area to post.