SODASTREAM THIRST

first off all the number on cylinder don't exist! then the PRETORIA NUMBER YOU GET TO SOMEONE SAYING HALLO HALLO HALLO....ALL THE TIME! I AM FRUSTRATED I AM SITTING WITH A CYL 30 AND NO ONE SEEMS TO KEEP IT ANYMORE FOR EXCHANGE AND TO TOP THINGS UP YOU DONT GET HOLD OF SODASTREAM TO ADVICE WHAT TO DO ? CAN I TRADE MY MACHINE IN FOR NEW VERSION AND PAY A BALANCE OR WHERE CAN I EXCHANGE THE 30 CYL....I AM FROM POLOKWANE LIMPOPO AND WENT TO ALL OUTLETS LIKE SPAR ETC WHO USED TO KEEP 1