New outlook email web client is borked

Seems to be broken. Very slow to recieve emails sent direct to it and does not seem to be checking my external O2 email account like hotmail used to. In fact switched back to using hotmail and still not checking O2 anymore.

Seems like it takes a few hours to sort it outself out. But I did need to edit my O2 external email settings (without actually changing anything) to prod it into start checking it.