Is that the only channel? Does the error message appear on screen or just the icon on the guide? Are you using the Pik TV box, the iOS / Android app, or the Apple TV app?
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Are you connecting to Pik TV on your Apple TV on your home internet? The content provider has restricted availability when away from your TELUS home internet, so if you're on a different internet connection or a VPN, it won't show up in your guide.
I just checked on my Pik app for Apple TV, and Chek TV is showing up in the guide and I'm able to watch.