MTN - Not crediting accounts with required data

This is my email to them on 7th Surprise- NO REPLY TO DATE <br> I have now tried for past two days to get in contact with you and each time I hang on for over 15 min - and telling me via a voice recording \we are experience high call volumes"is the same excuse every day and all the months / years prior trying to get hold of the MTN call centre. I am writing to you to sort out my mother's account as it seems she is not receiving her data as per the contract she is paying for?<br> Contract she upgrade too on the 01st May 2015<br> Samsung Galaxy Core Package <br> 100 anytime min<br> 200 sms<br> 300mb data <br> No sms since May received from MTN to say your package has been updated with 300mb of data"