Do you have enough storage capacity for the video being taken @pappan ?
If so then if this was my situation I'd first try clearing the phones system files cache by turning the phone off and then from a set series of button presses go into the phones system files.
If that didn't help then back up and remove any relevant Sd card and factory reset.
If that didn't help then seek hands on at a Samsung Experience Store / Samsung Service Centre
Daily Driver > Samsung Galaxy s²³ Ultra 512Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
