My phone (iPhone 16 Pro, previously running iOS 18.5) was fully charged (almost 100%) before I started the update. However, after the update attempt, the phone doesn't boot to the welcome screen and only displays a red battery icon, indicating a lack of charge despite being charged earlier. Additionally, it won't enter DFU mode. Can you let me know how much seconds should I wait for step 6 ?

Thanks .. I did retry a couple of times and managed to get into DFU mode.. Thanks Jordan!!