Read the scope of Record series
The current scheduling help says to choose the plus icon and Record series when that option is available. It describes subsequent episodes on the same channel being recorded automatically. A series name appearing elsewhere in the programme guide does not expand that instruction into a service-wide recording rule.
Use the rebroadcast example to diagnose the gap
Suppose the main showing is on one channel and a later repeat appears on a sister channel. The repeat appearing in the guide is not proof that the first channel’s series rule should create another copy. Compare the actual channel and episode before assuming a missed recording. If a separate showing matters, inspect whether that individual programme has an eligible record control rather than relying on the title alone.
Being offline is a different condition
The same help says recordings are created even when the viewer is not online at broadcast time. Keeping a phone awake therefore does not solve a channel-scope or repeat-exclusion issue. The general recording guide separately qualifies eligibility by country, plan and broadcaster licensing. Where rights prevent recording, the general guide says the record button is not shown. Report the scheduled event, channel and chosen recording option if an expected first showing is absent. This is a source-based explanation of the scheduling rules; no account, recording or broadcast capture was tested.