The only eay to solve this problem was changing mainboard.
When I reset my bios setting to default, the thunderbolt port doesn’t recognize anything. I can charge phones or other device by thunderbolt port, but It cannot recognize USB storage or thunderbolt dock. I did anything to fix this. There are what i did. 1. BIOS; thunderbolt setting is all clear / updated 2. Reinstall Window; already did 3. Dell diagnose(pre-boot system performance check) result  1) USB devices: all clear  2) PCIe Bus       Bus 01: Link Trained x1, PCIe slot 04       Bus 02: Link Trained x1, PCIe slot 06       Bus 03: Link Not Active, PCIe slot 08 empty       Bus 6E: Link Trained x4, PCIe slot 12       Bus 01: Link Trained x1, PCIe slot 04       Bus 02: Link Trained x1, PCIe slot 06       Bus 6E: Link Trained x4, PCIe slot 12       Ended: (Diagnose date, time…)       Test Result: Pass 4. Thunderbolt driver update  1) controller driver: ok  2) firmware: cannot update What is the problem…?
Xps13 9370 thunderbolt port disabled