During "compose email", email refreshes and is lost.

If I write an email for more than 2 minutes, it vanishes.  It is not saved, it is not in drafts or trash or sent.  I tried hitting "save" after a sentence, but it says the connection is interrupted and I have to logon again, however my email is still sitting there.  I don't have this problem any time except when I am composing an email.  I am running Windows 10.