Continue your journey after a KVB employee revokes your ticket?

Hello, I was stopped on the tram in Cologne from Bensberg to Cologne. The card reader couldn't recognize my bus ticket (VRS Student Ticket). The employee said my ticket would be confiscated and I'd get a replacement ticket. But then another employee said that because the card couldn't be read, they couldn't issue me a…

Price levels from Cologne to Düsseldorf Airport via Leverkusen?

A ticket from Cologne (Deutz Messe station) to Düsseldorf Airport with the regional train costs 11.30€ in price level 5. However, I noticed that a ticket from Cologne to Leverkusen costs €3.80 (price level 2a), and then another €5 from Leverkusen Mitte to Düsseldorf Airport (price level 3). So the total is only €8.80 instead…