I’m not receiving any emails other than automatic ones

Over the past few days it's came to my attention that many people have been emailing me but I haven't received anything other than automatic messages from tumblr, twitter, etc. I've checked all the junk and block settings and everything's in order I'm just not receiving a lot of the messages I'm supposed to receive. Is there any way to fix this and retrieve all those emails? The emails are really important ones from universities, school, etc so it's really important for me to retrieve them please.