Webhook synology Surveillance Station

I am trying to setup a webhook in surveilance station, to trigger an action in my home assistant (display livestream on my google hub) when there is motion detected by the synology.
Setting up the livestream is done, with an other trigger it works, but i cant get it working with the synology.
I have done this:

Does someone see what i am doing wrong/still need to do?

I didn’t do anything, and it started to work spontaneously after a day. But now I get webhook messages, also when synology not is recording.