SRT protocol has a special StreamID format that isn’t similar to familiar to us RTMP.
For example, you have created a stream called “mysrt” in Flussonic:
Now you should enter StreamID like this (yes, it’s very important to keep #!::r= symbols!!!):
Or full form for OBS:
More details here: https://github.com/Haivision/srt/blob/master/docs/AccessControl.md#standard-keys
Flussonic documentation: https://flussonic.com/doc/live-streaming/publishing-via-srt/