No emails on phone since package upgrade

I upgraded my package recently to a more expensive one and have found that I am unable to send or receive any emails as of 30 November...the last day of my previous package. I have been told that my phone is in need of an update, that there is *******ion and that it is a Telkom fault. The truth is that I am getting emails on all other computers, tablet as well as alternative phone, just not on the one applicable to the upgrade. I really need somebody from Vodacom to help, the shop assistants show very little concern at all.