My Lumia 640XL only has 260MB free on phone. The micro SD 64Gb almost half free. The phone is misbehaving. Some apps shows no memory available, the camera does not display button to take photos, and a lot of problems maybe related with almost no available storage. But I cannot remove apps from phone/sd. The storage never finishes to show the app list. What to do? Reset? Again?
First step is to uninstall apps you know are big and also apps you can restore data for (many apps store data in your OneDrive so you're safe).
Then put the apps on the memory card by default. Apps on the memory cards shouldn't complain when there's no space on the phone itself.