[Help] Flashing OxygenOS on OnePlus 13 (1to) from AliExpress (Lock State: locked)

Hello everyone,

I just bought a OnePlus 13 (1TB version) from AliExpress. I was super excited to try it out, but after spending just 1 hour on ColorOS… I can't take it anymore. It's full of Chinese bloatware, ads, and I can barely understand anything. It's really frustrating.

So, I checked a few guides on how to flash OxygenOS, and it seemed pretty straightforward. But when I tried using ADB, I saw:

Lock State: Locked

So I couldn’t flash anything. After doing a bit more research, I found that my device shows:

State: 0 – which apparently means the region lock is activated but temporarily disabled.

Does anyone know what I can do from here to be able to flash OxygenOS? I really can't stand ColorOS even though network and basic functions seem to be working fine.

Any help would be greatly appreciated