Terrible service

I paid R245 for a standard letter to be delivered to Ceres as its an "outlying area". I chose and paid for an OVERNIGHT service! As I sent it on a Thursday morning - so logic says - it should have been there on Friday. But NO - by Monday afternoon it was still not there. I phoned to inquire and they told me it was a "2 day service" despite the fact that I paid extra to have the OVERNIGHT service. If that service doesn't exist to certain areas - don't offer it and don't charge extra for it!!!! And then don't argue about the definition of OVERNIGHT!