I've got a new X-cover5. I charged it to 40% at lunchtime then plugged it in again overnight. In the middle of the night it made a persistent warning noise. The screen was full of small text that began "unplug the charger immediately" so I did that and the message disappeared, and the noise stopped. I'm aware that overheating can be a problem so I felt the phone and it was not hot. What can I do to avoid being waken up again?
Also you mention a new case I would pick something hat is protective but breathable. Also phones always heat up when charging but that's only when they are being used.
If you have another appliance that you can charge through it, give that a go, to see if a new appliance has a charging fault. If all is well, then it would point to a phone fault.
True, nothing should be left charging overnight while you sleep. It's asking for trouble especially if it's on a bedside table near you and catches fire. If the flames don't get you the fumes will.
