Some users are unable to verify their phone number both for OBC and Stripe verification because, for some reason, they are unable to get the verification code via SMS. But they regularly receive SMS with the phone number. I'm not sure if this is peculiar to some countries. I suggest alternative means of verifying the phone number be added, such as an automated call where the user could be required to say their name once they answer the call. It wouldn't take more than 3 seconds. Or maybe some other requirement. I think there's some software that can be used for this to avoid call costs to different countries. An alternative could be sending the verification code via WhatsApp to that number.