Thanks for your post and welcome to the forums. It's really great having you on board with us in the Community
All of our On Demand box sets are reviewed often to ensure we are making room for new content. When we obtain a licence for one, it only lasts so long.
Once the Walking Dead expires you'll no longer be able to view the box set I'm afraid. It is certainly a popular series so I'm sure it will be back to view soon enough.
Apologies for any inconvenience.
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