They stole my parcel!!

On Monday (30/10/2017) a friend of mine from Durban used Speed services couriers to send my brand new iPhone 6 I had bought. The destination was Marshalltown post office in Johannesburg. I collected my parcel today (01/11/2017) at the Post Office here I Joburg only to find out that the box which contained my phone had been opened and the phone no longer inside! ****** by their own staff!! They left the charger and the iPhone key and only took the phone! I complained to the manager at the Marshalltown Post Office on Sauer street and she just gave me an A4-size piece of paper to fill in with my complaint and she says that's the only thing she can do and she'll send to Speed Services. Apparently this is a norm by the staff of these 2 companies and I'm planning to stop it now! I want my phone ASAP and if this doesn't happen within the next 7days then I'm taking it to the highest level possible. MARK MY WORDS!!!