These episodes are not "new" and therefore if your series link is only set to record "new episodes", your box correctly doesn't schedule them.
If you check the episode precis, you will see a "first aired date" which is the giveaway. Check your SL settings, and if you want your box to record re-runs, change the "Record" field to either "New and reruns" or "Record everything".
It looks like the episodes you've missed are available on VOD - I would guess this would be available to all TV packages for 30days from broadcast as "CatchUp" and then perhaps beyond that as a "BoxSet" if your package includes those.
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