Send the following on WhatsApp
Continue to Chat【疑惑?】重新安裝系統後,Office 2021 家用及中小企業版 一直提示【此產品已安裝在其他裝置上】 https://im5481.com/2022/04/12/%e3%80%90%e7%96%91%e6%83%91%e3%80%91%e9%87%8d%e6%96%b0%e5%ae%89%e8%a3%9d%e7%b3%bb%e7%b5%b1%e5%be%8c%ef%bc%8coffice-2021-%e5%ae%b6%e7%94%a8%e5%8f%8a%e4%b8%ad%e5%b0%8f%e4%bc%81%e6%a5%ad%e7%89%88/