SMS Authentication Assistance in Vietnam

I am seeking a freelancer to assist with SMS authentication for our Vietnam site. We have already completed passport verification, but we need help with verifying existing phone numbers in Vietnam through SMS code verification. Due to the difficulty of obtaining a local phone number without residing in Vietnam, we require someone who can facilitate this process for us.

Key Requirements:
- Verify existing Vietnamese phone numbers via SMS code
- Ensure the verification process is seamless and reliable
- No specific preference for service provider or API, open to suggestions

Ideal Skills and Experience:
- Nothing.

If you help me with this task, please reach out with your proposal.