USB Module has Sharpie on PCB

I have had my Framework 13 for quite a while now, but just recently the USB-A module began throwing power surge errors regardless of what port it was connected to.
I opened just a few minutes ago and saw the writing ‘SX’ or ‘5X’ (or the reverse).
See the attached picture for a better idea of what it looks like.
Let me know if this is normal.

Just opened mine up and it only has a small black dot in sharpie. Though I wouldn’t put much stock in either marking meaning anything.

maybe a quality check signature