API call PUT to /Notifications

   1Hello ! 

I'm trying to get rid of the unread notifications. I have about 2000 notifications to read, which are solved right now, so I don't need them. 

Impossible to get rid of them from the interface: cannot filter by "is read". The filter is not showing any column for this module.

Clouded solution so I can't create my own filter. 

Usualy I just do those massive updates with an api calls loop using a small C# programm:

" For all notifications ID where is_read is false {

    is_read = true;

}

It works, on the api call GET for all those notifications, all of the is_read fields all "true". But on the interface, I can see them as unread. 

Is this a known bug ?  Is there something I'm not doing right ? 

GET COUNT result for the is_read = false field:

{
    "filter":[
        {
            "is_read":"false"

        }
    ]
}
{
    "record_count": 0
}
View on the interface of all notifications - as you can see, there is still plenty of "is_read" = false: 
Thank you, hope my question is clear!