GetYourGuide Refunds Only Half After Canceling Eiffel Tower Tickets

I purchased two tickets through the GetYourGuide app for access to the Eiffel Tower summit on March 7 and paid a total of $283. I canceled the reservation through the app a few days before the event date, around March 18 (it may have been one day earlier or later).

After the cancellation, I noticed that I was only refunded the amount for one person, which is $142. Even though I made a reservation for two people and canceled it within the allowed time, I do not accept that only half of the amount I paid was refunded. I also did not receive any explanation regarding this issue through the app, and I did not have any communication with customer service.

I request that the remaining half of the total amount I paid also be refunded to me, meaning the full payment for both tickets should be returned without any deductions.