Consistently unable to switch, upload or create worlds in Realms on Jave

Over the past 24 hours, I have been unable to consistently switch the world my realms account is showing, though it has occasionally managed to switch. Neither switching in game nor using the minecraft website work.

When trying to create a new world in the third slot of my Realms account (currently the active one but without ever having had a functional world) I receive a failure message, even when I use no datapacks or set seed or custom game rules, only defaults. Attempting to upload a single player world also results in failure, with the statement that it’s 100% uploaded, but “Upload failed! (-1)”

I have received various other error messages (including one that continued past the screen’s limits), experienced both immediate failure and failure after long “verifying world” or “creating world” screens. I have tried restarting minecraft and my computer and my internet. Prior to this, everything seemed to work quickly and easily. Now it hardly works at all, and only if I can switch to one of my older world slots (not a guarantee).

Any help resolving this is appreciated.