There are a bunch of yt videos on this topic, some of which are fairly recent. I looked at a few, and most of their advice seems pretty obvious, but maybe you'll be able to identify your snag.

I've created (or helped create) a number of non-China accounts myself, including a few using Google Voice numbers (connect your device to wx anyway you please; receive verication code on your computer), so you could always try to start completely from scratch (i.e different number, different phone).

In any event, I highly doubt they are trying to throttle new registrations because that would undermine their core mission as a social media platform.

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