Fedex service sucks

Fedex courier company cheats the customer. There are number of complaints against the service that they provide yet management do not bother customer complaints. They do not answer their phone that they provide on the invoice. I used them and they deliver to incorrect address and without my sign they handed over my stuff to someone else. Kindly take the action against them. They charge customer extra saying custom duty bla bla but that payment go to Fedex account not the custom duty.