FedEx poor service

I purchased an item overseas which unfortunately was handed over to FedEx to finalise the delivery to its final destination. What an absolute joke of a courier service. The item was handed over to them on the 20th of January 2021. 1st they bungle the invoice cost to work out the duties... The duties is more than what I paid for the item. I informed the invoice is wrong on the 21st of January 2021. I have been mailing those people and calling for weeks now. It's now the 2nd of March 2021 and they have not bothered to fix their mistake and they refuse to give me my item. Their service is the worst I have ever experienced. They don't seem bothered at all to rectify the issue. They have a don't care attitude. All they do is just forward my requests to the same people who have not responded in over a mo th now. Useless...