iCloud sharing is not working

My device is iOS 8.4.1, another device should be iOS 8.2? not sure...

The last time I used it is about a week ago, and it worked, but yesterday I tried to shared a photo with my girlfriend, and uploaded a photo in album created by her, the photo can not be uploaded, but I can uploaded it to my own created album (shared), however, she could not see the photo.

When I tried to create a new shared album and invite her, she clicked the link, and subscribed, it said "This album is no longer shared", but the album is SHARED! Also, the "Subscribers can post" are both turned ON for both devices.

And... I can not insert the image in this question.... Apple, ......

So now, I got confused... Can anyone help me?