It is not possible to get refund for forgotten changing of a subscription. You can change it by yourself in flex basic.

Hi! Yesterday, 06 dec 2024, I went from Groningen to Amsterdam. First I bought a 40% discount ticket, for co-travel with my partner, but it was out of the off peak zone, so I had to by another one after. 
 

At the end, I bought two tickets but just use one. Can I received a redound for the 40% discount ticket that I bought but didn’t use? 
 

Thank you for your help

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