Is your subscription directly with Paramount or through Roku? Were you watching through "The Roku Channel" (same as "Paramount+ on RokuChannel") or using their standalone app?
If you have a subscription directly with Paramount, you should be using their standalone app (not the one that says, "on RokuChannel"). If your subscription is through Roku, the subscription is tied to the Roku account, so the new device must be linked to the same Roku account as the previous one.
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