This may not be directly related to SEO, but it does have some connection. I am curious about your recommendation for obtaining a US phone number. I haven't been active on YouTube recently and it appears there have been some updates. I am reaching out here because the members of this community are more informed on this topic than other forums.
You’re likely experiencing a change in YouTube’s policy, not a country-specific restriction. There are no known limitations on posting links in videos based on geographic location. It’s possible that YouTube has updated its terms of service regarding links in videos, or that there’s an issue with your specific account. It’s best to consult YouTube’s official help pages or contact their support team for accurate information.