MTN.and Hisense promises not kept

MTN the Glen went there to sign up for a new 2year contract by taking a HISENSE phone which they obviously support but on taking out the contract was promised a HISENSE soundbar which was promised by taking out the phone it's going on to 4 months now and no soundbar ,both the MTN and the Hisense agents say they don't have stock really WOW