Precision 5550, plugged-in not charging

I have had nearly same issues with "plugged-in not charging" error necessitating restart, when the charging would start in the computer off-state. I also have had my motherboard replaced twice, computer in depot service THREE times with further problems requiring a 4th visit minimum. I believe the USB-C charging design is not as robust as traditional DC jack, one possible reason being USB-C uses many small pins which are far more easier to break or overload, compared to a DC jack with surface contact area, and without delicate digital 'handshake' when connecting. this could be a design choice as Dell XPS/Precision line are much slimmer than competitors from Lenovo or HP and USB-C is flatter than round plug. But I am in the process of moving off Dell laptops, having had appalling customer service experiences and countless hours lost having to deal with their stupidity. Often their ProSupport have been unhelpful, WhatsApp service have sometimes been negative help requiring me to explain to the Indian team that their diagnosis is incorrect. Multiple times they tried to blame the customer for hardware issues in different subsystem, in my case they tried to claim my NVMe SSD was cause for an "Unknown USB Device (Device Descriptor Request Failed) error.