@moncef Netlify need to remove the domain from the other account manually.
To do this, they first need you to confirm you’re the domain owner by following these instructions:
https://answers.netlify.com/t/support-guide-verifying-domain-ownership-for-netlify-custom-domain/13765
The value that you would use is:
https://answers.netlify.com/t/i-cant-use-my-domain-after-i-deleted-the-account/129903
Once done, let them know by posting here to say it’s ready to be checked.
Then you just need to wait until they see your post, check the value and do the removal.