Buffalo Logistics are pathetic

I have ordered a parcel from SHEIN. Parcel was delivered at Buffalo Logistics on Dec 2. I receive message with the amount of Tax I had to pay on the 26th of November. I paid the tax on the 26th of November. Two days later, I queried the delivery, they said I must first pay the Tax. I told them that I did, and I send POP on the 28th Nov. On 5 Dec they send me message telling me I must pay Tax. I sent again, it got rejacted saying it must by PDF. Send AGAIN, making sure its PDF. I then phoned them. They said they see the message, but they can not open it as it is not in PDF format (I did send it in PDF). I sent again. I have phoned them, spoken to a guy. Since the 28th I have been sending them Whatsapp messages with POP, with no reply. They just keep on telling us that we have to pay tax before they will deliver. I have lodge a complaint on their website, adding the POP, but still no answer form them. These were all Christmas presents and we are leaving on holiday on the 15th, and we need the parcel BEFORE the 1th of December