Brief Answer:
It can be a callus or a cyst.

Detailed Answer:
Hello
Welcome to Health care magic.

I am Dr. Shama and I will be answering your query.

I reviewed your history. The common causes for hard movable lump on the upper side of feet are localized hardening like callus or cystic lesions like ganglion cysts.
Do write to me more details like
Duration of the lump?
Whether it is associated with pain?
Whether the skin above the lump is red and painful?

Most of the lumps on the feet are benign and may not cause any problem. The presence of pain and other inflammatory symptoms like redness, tenderness indicate that it is of inflammatory origin and it responds to treatment by the use of anti-inflammatory drugs.
If there is no pain or tenderness, then no need to worry. But if it is causing difficulties in wearing shoes, you can get it removed by surgical excision.

Do write back to me with more details so that I can answer your question more accurately.
Hope the information is helpful to you.

Thank you for writing to Health care magic.

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