Sadly, 3rd party booking sites like Hop2 are permitted to charge their own cancellation fees even when the flight itself is cancelled and refunded by the airline. This is why I try to never do business with them. From the Hop2 terms for "Force Majeure events":

Airlines might offer waivers to cancel, postpone trips or provide a refund to the passengers that might be accessible in case a specific flight that was affected is canceled. In case that you request any changes and/or modifications caused by force majeure circumstances are needed in your original booking (cancellation or modification), in addition to the terms and conditions of the airline company, our processing fees will apply.

• Our company services are provided in full by our agents, by services we mean processing any requests made by the customer to cancel, change the flight or refund requests, so for these services offered by our company a separate reduced fee will be charged.
• Our company has no influence and therefore cannot be held liable for the outcome of the cancel/change/refund process, which is a total discretion of the airlines. Nevertheless, the fee paid to process your request, which is not the airline's fee to cancel/change/refund the ticket, is a service provided by our company and cannot be returned.

If your bank and local jurisdiction have good consumer protection, there might be a little wiggle room in that you did not request the cancellation. However in other parts of their terms they specifically say that Iberia flights are to be rescheduled and not refunded when flights cancel, so be prepared for push back.