UPS- questionable integrity.No customer centricity. Terrible service delivery.

I was delivered an package only to realise that the delivery guy billed me the incorrect invoice and amount.I called UPS and spoke to two agents who could not assist me at all with receiving a refund even after I had sent them all the info.They told me that the person who deals with refunds is on leave.Come on one person in the whole company thats trained to deal with refunds? Who are they kidding.The team leader who was suppose to contact me is still calling.No communication from this people.Ridiculous.1 week later and no one can assist.This is absolutely unacceptable.UPS is *********** if it is so difficult to deal and assist there customers.I want my refund but they make it seem as if you need to beg for it. This is terrible that for such a huge company you have so much negative publicity.Should I then be suprised that I have call and follow up on money that is owed to me?Should I be suprised that I need to send follow up emails and copy the whole of UPS for someone to take note of my query? Probably not.