My order never delivered

Hi I ordered from Shein on the 31st of March my order arrived on the 7th of April to Buffalo logistics.Customs were paid on the 5th of April, I even attached proof of payment, Buffalo Logistics sending messages stating that I did not pay I have to pay again. I contacted them regarding the matter, the lady I spoke to promised to assist me. I sent an emails and whatsaap several times but still I don't get any help. My order never delivered to me till today.