@francescop47742 - My assumption is that your "Medium" eVar is set to an expiration greater than "Visit", and since you're combining two different reports (Marketing Channel and Medium) in your breakdown, you're seeing a combination of a new channel ("Direct") and an old/existing Medium ("banner"). This happens because on a Direct visit, there are no utm_ parameters, so the Medium report persists the previous value ("banner" in this case) even though the channel has changed.
- Referrer=[does not exist] - Marketing Channel=Direct
In visit 1, your reports show what you expect. In visit 2, the channel changes to "Direct", but since there's no utm_medium value, that report does not change, and you see "banner" when doing the breakdown shown in your question.