cant provide i formation

Got note 4 in March, in august battery failed speaker just stopped. After months of trieng to find someone that can fix my very expensive phone Samsung collected it on the 27 November. 2 weeks ago I sent customer care an email and was told they will let me know when it is finished so I can collect it. A week ago I followed up with them and now they can't tell me where my phone is. They say it is with the courier company who right now is to busy to find out where my phone is in the system. For the past week I have been asking and still have no idea where and with who my phone is? I told them I am leaving to go overseas on Monday for a long period and need to get my phone before then, but yet they have not made any effort in locating the whereabout of my phone or informing me of what is going on! This is unacceptable, how do you give a packet to the courier company without a tracking number so your client can follow up?