Hi Stuti Srivastava,

After you have successfully filled the application form, the IIT Bombay will send you a mail for confirmation. They will also send you a mail if there is any defect in your application form which you have to correct on their portal by logging using your username and password. Once logged in, you have to detect the defect in your form by clicking on change applicant details.

since you have already corrected once, and if you have received no more mails from IITB then you do not need to worry. If they send you a mail regarding your photo again, only then you will be allowed to change it.