I made a mistake while filing my n400 form. Need help

I am not sure that I understand what you have done. The N-400 asks for all names that you have used including nicknames on page 2, part 2, item 3. If you did not disclose a nickname or other name, you can do so at the time of interview as the officer will go over the form with you. I do not know what you mean by “added details under previous name”, but honesty is generally the best policy in immigration interviews. Due to the limitations of the Lawyers.com Forums, Alan Lee & Arthur Lee, Esqs.’ (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.