Hi Ravikumar,
When I followed the first four steps in your reply, this is what I saw for each of my children's accounts.
I had already read that forum post you linked. I created their accounts so they could play Minecraft, we do not use Microsoft software, so I am not sure about the second part of your reply "Log in your account on the device then go to Control Panel > User Accounts > Manage another accounts. Check if you can modify the password. If you still can't change the password, go to https://account.live.com/password/reset."
Whenever I use that link for the password reset, it asks to reset the password for my parent account. When I try to reset the password for my children's account, I enter an email address and a code is sent to the address. When I enter the code, it asks me to submit an account verification form, I enter all the information I can, but then receive an email with this:

I have nothing more to add to the verification form since my children have never sent emails from their accounts.