FEDEX NO RESPONSE & POOR SERVICE

As a company relying on FEDEX, what a disappointment. Consequences we are not proving our customer with the goods ordered. We have been phoning numerous phone numbers with no response. We have even sent numerous emails to the person handling our goods. (Mashudu Tharaga' <***>) We have been trying fr over a week to get hold of ANYBODY at FEDEX. How do we resolve this issue?