Burn, deep throb pain in soft area between inside ankle & heel. I have b -12 def neuropathy. Better when wrapped. Veins, clot? Left foot.

Ankle pain. Sounds like neuropathic pain which may be related to peripheral neuropathy or superimposed "tarsal tunnel syndrome". Treatment may involve removing compressive forces from the area (shoes), or controlling movement of ankle(orthotics), and/or the use of medications specific for the pain from nerves. Also in the same area are the tendons the go to your medial foot, and toes, can be tenosynovitis.
Ankle / Heel pain. Nerves do not work well without vit b's. I am thinking about vit b 1, 6, 9 and 12. It is difficult to absorb vit from your diet and if you are diabetic you will urinate out 16-20 times the vit b 1 of non diabetics. So if from vit b you will need supplements not just vit b 12. There are drugs that can help. This may also be a tarsal tunnel syndrome & you would need to visit your local podiatrist.
Be seen. Multiple potential causes, among them are abnormalities of the posterior tibial tendon, which lies in the area you are describing. Don’t hesitate to be seen for an accurate diagnosis.
Doubt clot. The area that you describe is most unusual to have a clot and even if it were to be a clot the treatment would be heat to the area, ibuprofen and ace wrap or support hose. It would be very difficult for an ultrasound to visualize a clot in this area. Most likely something else is causing your pain.