Charger cable starts sitting loosely in the phone socket/connector after a while

I see two options for you:

  1. Contact support and plead for a warranty ticket. If Fairphone grants you a replacement, the whole mother board would be replaced, resulting in an unfortunately high waste of resources. :frowning:
  2. Consider repairing the USB socket yourself (or let it repair by a phone shop / repair shop), as described here.