VODACOM NOTIFICATIONS ARE HARASSING

Over the past 4 weeks Vodacom keeps sending intermittent notifications (some days and nights more than 20!) to my cell phone, saying that my Vodamail email has been signed out. I have called the call center several times to get the matter resolved since the notification messages have become an absolute nuisance. The voice biometrix system (voice recognition to ID the caller) has stopped working as well, and keeps asking for a new validation every time I have been calling in to the Vodacom call center over the past 2 weeks. Is there really no-one at Vodacom who can resolve this harassing notifications and get the biometrix system to function like it used to for years? If not I should honestly consider another service provider since my contract is due for renewal anyway