Vodamail email not working

For the past 3 weeks I am unable to connect to my vodamail email via my laptop or desktop . Every time when I try to log on, I get an error “Service error has occurred”. When I refresh , it logs me out. The funny thing is that I get my emails via my iPhone, and I’m using the same WIFI connection. I just don’t understand what’s the problem. This has become annoying. I have called the call centre numerous of times and has not received satisfactory results. I have even tried to logon with different browsers. Can someone urgently attend to my query?