Brief Answer:
It seems to be dark circle under eye or bruise.

Detailed Answer:

Hello,

You probably have a dark circle under your eye.
Stress, lack of sleep, dehydration, less nutrition etc., can be cause for that.
For that, I can suggest starting practice following things:
_ Take enough sleep of 8 hour
_ Elevate head during sleeping by putting a pillow
_ Ice cube wrapped in a cloth can be applied over it
_ Avoid excess heat exposure and wear a face mask while traveling in sunlight
_ Maintain hydration with lots of water
_ Cucumber slice can be put over it for 15 minute daily
_ Fruits and green leafy vegetable to be taken more

If no improvement then you can Consult a dermatologist for examination of affected portion.

Kindly mention any history regarding trauma to eye if present. If similar lesion present elsewhere in body then also acknowledge about that.

Hope I have answered your question. Let me know if I can assist you further.

Regards

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Brief Answer:
It can be due to ruptured or dilated blood vessel under eye skin.

Detailed Answer:

Hello,

According to provided image it seems to be dark spot or dark circle under eye skin. The skin below eye is usually thin. So whenever blood vessel dilated or ruptured it can be seen through skin.

You can practice instruction given by me in my previous answer.
However you can consult another dermatologist as approach of your previous dermatologist was not good according to history.

In addition to above prescribed home remedy in my answer, you can be prescribed vitamin E capsule(antioxidant) and topical Aloe Vera cream as well.

Consult dermatologist and get prescription accordingly.

Hope I have answered your question. Let me know if I can assist you further.

Regards

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