Notifications json api


Hi everyone, I have a question about notifications.
From /notification.json api I got 6 unread notifications. types are 1,2,6,6,6,2. so 3 unread msg and 3 else.
then I click on the icon, the “light blue” bubble disappeard immediately, even though the msg not read yet. from json api, they are sill unread and in web still ‘light blue’.
So my question why it behave like this and how can i fix this ?

Thanks in advance.

here more screenshots. the ‘light blue’ bubble disappear?