PLEASE STOP CALLING MY MOTHERS BOSS !

I'm currently paying for my Mothers account which she opened in March 2019. The first time she spent around R2000 credit and towards end of March and selected the six month payment plan. we continued to shop in April and requested a 12 month plan in order for me to afford the installment . Every month I'm advised the account is split in two ( 6 and 12 month plan). On 26 May I went to Braamontein branch to make the payment as usual and requested for one payment plan . The manager called the head office and was advised that I can opt for the 12 month payment before paying . They advised that we call the head office first and request that they allocate the funds to settle the six month plan .now last month I went back and was told it is not possible .What upsets the most is that Truworths keeps calling my Moms boss to tell her that my Mom hasn't made payment. this is embarrassing and wrong in many levels . I am very upset and would appreciate if they stop calling my Moms boss and contact me as the payer. This is causing conflict at home . I pay every month an amount of R700 as this is what I can afford!