Dear Mr. Pandey,
Thank you for writing to us. The reasons for your son’s poor performance could be many and it is difficult to infer them without having a conversation with him. May be because of the frequent moves it is difficult for him to settle down in new surroundings, and this could lead to a loss in confidence. But this is mere speculation and I don’t want to guess. I understand how worried you must be as a parent and I would try to resolve your issue to the best of my capacity. Where are you located at present? May be I can find a professional for you whom you can go meet face-to-face with your son.