DSV delivery service FAILURE

I am a Unisa student and received an email 3 weeks ago to say that my address is insufficient for DSV to deliver my study material. This is firstly ridiculous, because I have not moved and my study material has always been delivered to the same address. I even received my first batch of material at the end of January 2024 with no issues, but now there is an issue with the second delivery? Secondly, after following up several times and speaking to more than one customer service agent, no one can tell me where my stuff is? I was told 2 days ago that it was delivered - it was NOT delivered to me and now they do not know where the delivery is. I am so fed up with not having a proper contact person and NO ONE can tell me who signed for the delivery because only my name is on the delivery note - no signature, no delivery time and no person who can help me get my stuff. How am I supposed to start / continue working on my studies for the year???