Chair with wheels for sim

hi, i have this office chair with wheels that i use for sim racing. yesterday i received the moza r5 steering wheel with the pedals (and brake kit) and i can't brake properly because the chair slides backwards. what do you recommend to make the chair usable? thanks

hi, i have this office chair with wheels that i use for sim racing. yesterday i received the moza r5 steering wheel with the pedals (and brake kit) and i can't brake properly because the chair slides backwards. what do you recommend to make the chair usable? thanks