stolen belongings in gym! help asap?

i was at the gym and put my wallet and phone in the locker as usual. when i went to the locker room to get my things the locker was open and my things were gone! the guy that works in the locker area is the only one with the keys to all the lockers but he apparently "went on break"

i complained to the front desk and they said there was nothing they could do about it! wtf im soo pissed, isnt that theyre responsibility??? its not like my phone got lost, it was stolen alont with my wallet which had my credit cards, money, license and personal information. wtf do i do? i already cancelled all my cards and i tried calling my phone but it goes to voicemail. i cant even think straight right now! is there any way i can get my things back??