Upgrade has stalled and I'm left with no emails - please help!

Yesterday I tried to do an upgrade to eM client so that I can connect my google calendar. However it is stuck on the 'Going Offline - this may take a while. Please help as I’m now stuck with no emails. The upgrade will not work - it’s asking me to renew or downgrade. However I don’t know how to downgrade OR renew the licence. When I click ‘Proceed’ I just get the 'Going Offline message. If I can’t fix this today I will be forced to use another provider!