@x1818z
You can use a USB adapter that is able to provide 5 volts and 1 amp of power, but all adapters are different so make sure it provides that specific amount of power. Some customers reported the camera constantly rebooting or not powerilng up at all using different voltages.
It would be best to request a replacement part from us. The links below will show you how:
How to Create an Account on the TP-Link Warranty Portal
https://www.tp-link.com/us/faq-2353.html
How to Register a Product on the TP-Link Warranty Portal
https://www.tp-link.com/us/faq-2355.html
How to Request a Part on the TP-Link Warranty Portal
https://www.tp-link.com/us/faq-2356.html