I managed to lock myself(iPhone Disabled, Forgotten my Passcode) out of my newly purchased iPhone 12 Mini, fortunately I have a bit of experience when it comes to troubleshooting iPhones, but these newer handsets is a bit different from the older models since they generally have a different way of navigating thru, especially that the Home Button are now out of the new iPhone's design.
This article resolved my issue: https://support.apple.com/en-in/HT204306#restore
Though I have employed the help of the Apple Hotline, a rep called me up, they seemed to be at a loss of the newer steps to restore the iPhone 12 series models. Just be ready of the following items, coupled with a lot of patience to go along....
1.) PC/ Laptop: Make sure to have the latest iTunes on your Computer
2.) Check your cables, you can either use the newer USB-C type or the earlier USB to Lightning Data/Charging Cable, since this depends on what connectors you have on your computer
3.) Follow the SPECIFIC steps mentioned on the link
4.) iPhones may needed to be Updated to the latest IOS before they could go thru the Restore(Factory Reset) step in order to unlock your iPhone
5.) With patience and perseverance, your phone may become unlocked again... as what happened to mine after an hour or two of wait.
I hope this helps!
Have a great day ahead!