correct NOB in ITR-4 under section 44ADA for software developer

Dear Experts, I am working as unregistered freelance software developer. I filed ITR-4 under section 44ADA. I got an email from CPC Bengalaru that the ITR is defective and the error code is 89 which tells that "The provisions of Section 44ADA not applicable to the taxpayer. The nature of business code in Sch NOB is not a profession, and the income disclosed under Section 44ADA income is more than zero. Hence the provisions of Section 44ADA is not applicable to the taxpayer." The probable resolution suggested by CPC is "The provisions of Section 44ADA is applicable only to Professionals with nature of business codes of 601 to 607. Taxpayer is requested to furnish correct Return Form type,i.e.ITR- 3 or ITR- 5 as applicable. If the Income has been disclosed under incorrect Section, the correct Section of the Schedule BP may be filled. If the Nature of Business code entered in the Return filed is not correct, the correct nature of business Code may be entered in the Sch NOB and the Corrected Return may be filed." In the Nature of Business I had used "0709-I.T. enabled services, BPO service providers" which is wrong as per CPC. To correct defective ITR-4, I should use Nature of Business as "607-Others". Is my understanding correct? Do I need to correct anything else apart from modifying NOB? Best regards Arvind