Flight got delayed and missed my tour. How to refund?

I was in the airport to check in on my flight and at the last min., the flight was delayed and I was asked if it was fine with me to upgrade my flight to a higher class but on the volgende evening. I declined because I had a social dating tour to attend that volgende morning. I already contacted the agency if I could refund my fare but I still have to wait for the response. But the ticket was something I got separately. I don’t know how these things go and I was wondering if I can still refund my ticket? Need some help.