Poor service and not getting back to me with resolution

Poor service from Vodacom. In a years time this is the 3rd time that I'm getting billed for 2 handsets and only received 1 handset. March 2017 I upgrade and received new handset. I upgraded my contract in March 2019 and received new handset and after the upgrade was done I'm again being charged for 2 handsets. I urgently need clarification with regards to this matter because this is now the 4th time today I need to follow up this matter with no resolution as yet. They say they tried to phone me but no one has phoned me with any explanation. My reference numbers to this regards is 1- ********** ********** & 1- ********** **********