No response/feedback to query

On 03 Oct 2017, I phoned Std Bank Insurance Funeral Plan querying, among other things, why I was charged R 130 from March to July 2017, whereas I should be charged R 110.50. I was told that they would investigate and someone would phone me back with an explanation. Well, 3 weeks later and I have had no response, despite leaving 2 messages on the internet site asking Funeral Plan to phone me and sending 3 e-mails. My funeral plan policy no. FNR ********** 1. I have tried phoning many times but after holding on for at least 20 minutes, I hang up. Amazing how you are always experiencing high call volumes, no matter what time I phone. Please can this now be resolved urgently!!!