My Nokia 6.1 is also getting heated without excessive application working in background.
Nokia please resolve the issue we have trusted on u.
I have experienced exactly the same issues with my N6 2018 in the UK. As a addition battery used to discharge at abnormal rate.
After contacting Nokia and the supplier handest has been replaced without problems. I guess thebattery itself or charging/charge control unit was faulty. New phone works exceptionally well.
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