Unintended number change

Morning, I recently took a contract at Telkom about a week ago. I kindly asked the telkom agent who was assisting me to change my “already existing prepaid number” to a contract, so as to allow me to keep my number. They instead deactivated my prepaid number, thus I was then stuck with two foreign numbers: a new prepaid number (which replaced my old number) and a new contract number. I tried to go to the Telkom store but they failed to resolve this problem. I then tried to contact the customer service but they too are taking me to and fro, with no clear solution. I have been seriously inconvenienced and I am not getting any sober response from Telkom. I was not intending on changing my number. Please assist. This is surely my last contract with Telkom! Such incompetence!