iCloud storage says full even after deleting all my emails

I keep getting notifications saying my iCloud storage is full. So I decided to delete all my emails I don’t need. And yes I deleted from my trash too. My emails are taking up 3.5GB of my 5.0GB iCloud storage , so it states……. Even after deleting my emails, it still states my iCloud storage is full. I tried updating my phone since it was out of date & still nothing… I go to iCloud storage in settings & turn off the switch for “iCloud mail”, & still nothing changes. I even tried doing that & restarting my phone & performing a hard reboot. I need help. What do I do ?