Hello and welcome to the forum. So, you've only see the vascular doctor for this, correct? I'd see your general practitioner as well. Have you been screened for diabetes or anemia? These both can cause this situation as well. Peripheral neuropathy can cause this symptom you describe. PN can be the result of diabetes (diabetic neuropathy), traumatic injury, exposure to toxins, autoimmune diseases, inherited disorders, liver disease, and kidney disease.
I would continue to dig deeper but with your general practitioner at this time. https://www.cvmus.com/blog/why-one-my-legs-cold-touch