Complaint about laptop tech support in China for changing assets tag

I live in China and bought Vostro 5620 from China. I want to modify “assets tag” in BIOS, which is already entered last year when I bought back. So, I turned to your China tech team support on WeChat, but I received a very poor service feeling. The staff ID is 975. The staff told me it cannot be modified and changing assets tag in BIOS will cause irrecoverable damage to my laptop. How interesting, how ridiculous! I have already entered last year. What’s more, this tech support staff did not mention other tools published by your Dell several years ago: CCTK, SVCTAG.EXE

WHY? I cannot understand. She is the tech support staff. Why does she not know these tools? Anyway, can the assets tag not be changed once entered?