eBay購物後賣家要我提供身分證末6碼 - 網店

前兩天在EBAY上跟一個香港賣家買了電動牙刷頭
利用信用卡付款後隔天他留了訊息給我

Hello, sorry to bother you. Since the declaration required ID number, please
report on the first six of your ID card or the last six, please? Please be
assured that the information we used only the declaration.
THX， regards.

請問買家提供身分證6碼是ebay的官方規定嗎?
抱歉第一次在ebay跨國消費不太清楚~

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