I get the "Screen on/off permission required" and "Volume up/down permission required" notification after reboot too.
I try to make below setting to fix it,
1. Enter "設定" -> "協助工具" -> "進階設定" -> "音量增加與降低鍵" -> "所選服務" setting.
2. Change the "Voice Assistant"(default) to "MacroDroid Volume...