AT claims a channel does not exist even though it does

I’m trying to create a dynamic channel name with one of the fields, but when I test it, AT claims the channel does not exists even though it does.

This is the channel name definition:
image

And this is the error I get:
image

But this channel does indeed exist:
image

And it even appears in the list of channels when you try to choose a static one:
image

ideas anyone?

I already answered you in your other thread on this topic. Please don’t keep posting the same question multiple times.