"Use iCloud" toggle in Pages setting won't stay on

iCloud drive works fine on my MBP and on my iPhone, but not on my iPad. (All are properly updated.) I can toggle "use iCloud" on the Pages setting to green on the iPad, but when I go back to Pages, I still have no access, and when I check the settings again it has turned off . . . iCloud Drive is toggled on in the iCloud settings.

Thanks for any help . . .