I just tested and found that if you have a colon in the sheet name, you can only update one cell.
If you try to update multiple cells, you’ll get that error.
If you try to update multiple cells and remove the colon from the sheet name, it should update properly.
After some more research it appears this is actually a known bug in Google Sheets, and it doesn’t look like they’re going to fix it anytime soon. Best to just remove that colon or use one of the other workarounds.