Terrible service

I couriered a small package from Australia to South Africa, dhl quoted based on about a 1 week delivery time. It has now been over two months and my parcel has still not been delivered. I raise the issue with customer service and they assigned a staff member to investigate but each week I follow and I am just told that the staff member is unavailable and can’t help me. The parcel contained the engagement ring of my fiancé who passed away, and even though it was insured we part of the delivery service, which I payed extra for, was belittled by customer service for asking if they would write it off and pay out my insurance claim. They are unwilling to provide any detail as to when my late fiancés ring will arrive back home and insult me for suggesting that after two months of nothing that to pay me out for something I payed insurance for is insane.