Apple, through its "System Status" page, has just reported that some users may be having difficulty with some services of the iCloud.
More precisely, the company said that the Photos, O iCloud Drive it's the Grades are performing slower than normal. In addition, users trying to upgrade their iCloud storage plans may not be able to do so because of these issues.
Ma, of course, is working to normalize everything we'll let you know as soon as it's resolved.
Update 5/14/2019 s 13:27
This is a quick force: apparently everything is already normalized.