I have been having problems with Outlook for days.

I have been having problems with Outlook for days. It is on and off and just says 'Sorry there seems to be a problem. I've cleared the cache, tied other browsers and also a tablet. Nothing works. It is imperative I see my emails and can respond to them. Can anyone help? It seems to work very occasionally, but most of the time today it isn't working at all. Urgently need advice!