History Channel is one that requires you to be paying for it via a subscription to a "tv provider" service that carries the channel, such as a cable or satellite subscription, or a paid streaming service.
If you have such a paid service and have logged into the History Channel app on Roku using your HIstory Channel login credentials, try logging out and back in.
Roku Community Streaming Expert
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Ultra 4800 | Streaming Stick 4K+ 3821 | TCL Roku TV 43S245/C107X