Repair to tablet in warranty

I handed my Lenovo Tablet in at the Paarl Branch on 2015-04-09 for repairs. Was instructed to wait for six weeks before I make any enquiries. After several visits to their shop, as they do not answer their phone or respond to any e-mails, I received it back on a Friday afternoon - 2015-05-21. I only tested it the following morning as I was assured that it was fixed. The original problem was that it did not read its sim card but now the speakers and screen was damaged. Took it back on Monday 2015-05-25. Again I was informed to wait 6 weeks. Now 15 weeks later I am still without my tablet. In the meantime I am paying for a contract without the use of it for more than 3 months. When you do reach them you get the same useless excuse to wait for the repairs. But I must compliment them when sending out the account every month. Maybe they should rotate the accounting staff to the service department. I am fed up with them. I have been with them for more than 20 years but be assured this is the last contract with them. If they treat loyal customers like this beware what they will do to new ones. Good advice - STEER CLEAR.