New phone returned within 10 days which is faulty

My mother upgraded her mobile phone contract, received her new phone on 20 feb 2015. On 23 february she contacted them telephonically to complain that the phone is faulty and disconnects within 3 minutes while talking. The phone was returned to autopage welkom on 27 february where they told her that they have to send it in for repaires. If its returned witin 10 days werent they suppose to give her a new phone? When will they realise that not all of us are idiots? I had the same problem a year ago with telkom 8ta. All the mobile phone companies that i enquired with rep**** that if returned within 10 days, she should get a new phone. Just because they are elderly people, doesnt mean that they should be satisfied with substandard goods. When will she get her new phone? Her new subscription fee is already loaded to be deducted at end of march, but no phone yet. This is absurd and utterly ridiculous. Where has good service gone to? Is this now the new norm to give customers broken goods and then still expect them to pay, as if its new and in good working order?