Delayed Shein delivery

I ordered from shein and my tracking status says it is transfered to courier which has been like that for 5 days now and now they telling me my parcel is stuck on customs clearance and their delivery date is parlst due but the question is how when its already at their Johannesburg warehouse that time I'm just at Pretoria and the funny thing is that people who ordered weeks after me they already got their parcels and I need the parcel urgently before Friday it contains things for my graduation. This is really disappointing of Buffalo logistics, and worse part, they don't even respond to my 5 emails that I sent, and when I call, they also don't respond, so unprofessional for a company. They deserve zero stars for this.