Telkom falsely suing us

My grandfather bought a laptop for me on his name, when he passed away talk on told us they have closed the account in January this year, now they have given us three case numbers for not paying, when we call they say it's shows that the account is closed but they still investigating they will come back to us but we still waiting for that call till today since from last week Monday if I'm not mistaken...thanks for your help.