In reply to Yash_wanth12345:
You can’t override sequence_items being generated by a sequence using an instance override. This is because the sequence_items don’t exist at any specific level of the hierarchy. You can only use the type override as you have done.
It’s recommended to create a new sequence using the new sequence_item and override the sequence if needed.
EDIT: You can use the contxt argument of the create() function to use the hierarchy of the sequencer. See my below comment.