Squaring off SENSEX Positions

I am unable to square off my SENSEX option buying position held overnight using usual method of exiting the positions. Why is this so?

Intraday, we can square off.But if hold the same overnight especially SENSEX positions can not be squared off.Please suggest if I am doing anything wrong here.

@RAMESH_3198488 - Could you please provide more details, including any error messages?