SCHEDULE FA Query

I am employed by US mnc which is listed.
in hear 21-22 i had received RSUs from my employer and employer used sell to cover for deduction of income tax and sams is shown in my form 16 as percusite and while filing ITR, scheudle FA was missed, can i update that with ITRU filling for last year. Also note that i haven't sold any RSUs yet that are vested after sell to cover.
If not ITR U, what are other options available for me? I see lot of information about penalty of 10 lacs or 7 yr prison. kindly guide me as im novice in filing taxes. Thanks.