I'm pretty frustrated with Roku. I have found the same problem with other shows 😔
Your frustration should be directed at the content owners. They are the ones that decide what they will release and when. Roku can only show what the providers will agree to provide them. Perhaps the owners wanted a premium fee for certain episodes. It's been reported to happen before, when the content owners decide they don't want to release a complete series, or even a complete season, so rather than refusing to offer they simply jack the price for some of the content much higher than the rest of the episodes.
Roku Community Streaming Expert
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