Brief Answer:
Can be due to Plantar fascitis.

Detailed Answer:
Hi

Thank you for asking HCM

I have gone through your query. Is the pain under the foot ankle?
Or pain inside joint?
Do you have pain while rotating ankle joint?
Is there pain while pressing the foot to the floor?
Is there pain while start to walk after sitting?
Whether pain decreased or disappeared after walking for some time?
Is it only on one foot?
Do you have history of trauma/injury on foot?
Have you tried any medication?

Please update with above information.
I am happy to help you.
Thanks.

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Brief Answer:
Most likely it is Platar fasciitis.

Detailed Answer:
Welcome again.

Thank you for your follow up.

Your problem is most likely palntar fasciitis. Wearing heal pads or cushions in foot wear/ shoes is helpful. Stretching exercises of foot and ankle can be done . You can take NSAIDs like Ibuprofen for pain also. If no improvement then you can go for physical therapy. Physical therapist will advise you wearing night splints that stretches your arch foot and calf while sleeping. they will also help you to go for custom fitted arch supports if needed.
If there is no improvement then you can consult an orthopaedician for local corticosteroid injections.

Let me know if anything not clear.
I am happy to help you.
Thanks.

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