Hello Aspirant.

Since you have not mentioned where you want to change your registered mobile number, I can only give a generic answer and not a specific one.

If your query is regarding an application form, please know that universities mostly open their correction window for some time after receiving the forms. Universities may release a correction form. In both cases, you need to act accordingly.

If your query is regarding your official record in college after admission. You need to submit an application or ask for the procedure in the office.

Kindly specify where you want to make the said changes so that I can provide you with relevant information.

Hope you find this useful. All the best for your future endeavours.