I'm facing a frustrating issue with Yahoo's two-step verification process where OTP codes sent through SMS and WhatsApp simply aren't being delivered. I've checked everything: the phone number is correct and active, it matches my WhatsApp account, and both the app and my iPhone's OS are up to date. My recovery email verification works fine, so there's no problem with confirming my identity; it's just the OTP delivery that's failing consistently. I'm in Brazil, and I've tested this on both Wi-Fi and mobile data. I'm looking to understand if there are any known technical issues with Yahoo's delivery methods, especially using the WhatsApp Business API or if there's something specific about SMS routing to certain carriers in Brazil. Could this be linked to carrier filters, anti-spam policies, or constraints with the WhatsApp API? Has anyone experienced these types of silent delivery failures without any error notifications? I'd love to hear any insights or similar experiences regarding messaging infrastructure challenges.
1 Answer
The WhatsApp part of this is really puzzling. If you're connected to the WhatsApp network, your carrier shouldn't make a difference. SMS delivery is where problems typically arise. For instance, maybe Yahoo can't access a working SMS gateway for Brazil, or perhaps your carrier is treating their messages as spam. Another issue could be that your mobile plan blocks Short Code SMS. I often see that with certain providers. Have you tried Yahoo's Account Key feature instead? It's based on their apps, which might be more reliable.
You can actually set Yahoo to send verification codes to WhatsApp instead of SMS, which could work better in your case.