There are a few issues at the moment - can you describe what problem you are having? What device, what email programme, what browser if webmail, what error message? Don't post any personal details, of course.
Here are some of the current issues that appeared yesterday and are still ongoing to my knowledge (9 June):
Thanks for your post and for reaching out to us regarding your email issue. @MissPasko gave some very good links regarding what might be the issue. If it's the website then we would need to know what is happening when you try to access the webmail? Do you get an error message or what are the behaviours you are experiencing when you try to log in?