Invalid channel ID

Hello

I have a Grafana dashboard with a panel that i want to stream live data to. I’m using the Websocket plugin and I am able to stream some data into it. But it’s not working 100%. My problem happens when i select multiple channels from my panel (subscribe). If I cam pass variable values to the panel path like this: path: panel1/${var1.0}/${var1.1}/…

This works if i select the exact number of values to pass in the set variables of the path.

If I want to make it more flexible and knowing Grafana by default uses this syntax to pass multiple values in the variabe, i try to use the path: panel1/${var1}

But inspecting the browser tools I see there is an error while parsing multiple values (see image)

Why is it throwing this error?