Defective return u/s 139(9)

You can't revise return for the A.Y. 2018-19. However you can submit the correct return in response to your notice u/s 139(9).

can I change the ITR

Yes, you can change the ITR form.

You can change the ITR Form while submitting the return u/s 139(9)

NO you cannot change the ITR. You can only correct the errors in the ITR.

ITR can be changed if the return is defective.

We can only change the defects pointed out in the intimation issued by the department

(a) Download the ITR Form the Income Tax Department website.

(b) On the income tax return, select the option “In response to a notice under Section 139(9) where the original return filed was a defective return.

(c) Enter the reference number, available on the notice, and acknowledgment number and date of filing original return.

(d) Complete the income tax return including the rectification required.

(e) Generate the XML File and upload it to the Income Tax Department website

(f) Select “e-File in response to notice u/s 139(9)” under the “e-File” section and upload the rectified XML using the password mentioned in the notice.

(g) Confirmation message with an acknowledgment number appears on the Department on successful upload.

There is no condition that you can't change ITR even though I changed the ITR once.

ITR can be changed if the return is defective.