Mail app wont update my emails

For some reason my mail app won't update my emails, and refreshes to the emails (both read and 'unread') i had 3 days ago (Tuesday). It even recognises that the emails were received on Tuesday, so it doesn't have the days confused, so to speak. I changed my settings from 'show emails separately from subscriptions and social media' to 'show in the same folder' (inbox), and it adapted to that! But the emails shown are exactly the same! If i access my mail accounts (one is hotmail, the other is gmail) elsewhere, for example, online or on my phone, i can see that i have new emails, but they don't show up on the app. Is there a way to fix this?

Thanks!