Gym charges full fee whilst partially closed

8Andrea8

Hello all!
My sports club has charged me full fee for August and September, whilst not providing full access since they opened after the Quarantine: currently the opening hours are reduced, less classes and less spaces in classes and no acces to sauna/steam room. 

I have contacted them stating that I explained a discount, but they are not responsive.
They also have been running a deal throughout August, which allowed new members to join for 3 months for a fraction of our membership fees.
I don’t want to leave the club at this point, but I feel that it is not fair to be charged a full fee for a partial service in a club that is extremely overcrowded due to this cheap membership offer to the new subscribers. 
Are there any legal ways to receive a refund for what I feel is overcharging?