Y mail on my kindle fire hd

[AC Question]

Using Y mail on my Kindle Fire 7HD. It opens, works awhile then I get a message, "Y mail is not responding, do you wish to shut it down?" On both my account and the wife's. I shut it down, re-open it and the same thing happens. DRIVING US CRAZY!!! This started a month or more ago. Prior to then it worked fine. Anyone else with the same problem?