Send the following on WhatsApp
Continue to ChatiOS 15.0.1發佈后蘋果停止簽署iOS 15.0 降級不再可能 https://blog.wongcw.com/2021/10/09/ios-15-0-1%e7%99%bc%e4%bd%88%e5%90%8e%e8%98%8b%e6%9e%9c%e5%81%9c%e6%ad%a2%e7%b0%bd%e7%bd%b2ios-15-0-%e9%99%8d%e7%b4%9a%e4%b8%8d%e5%86%8d%e5%8f%af%e8%83%bd/