After Dutt attended PK's screening state government declared of conducting an enquiry regarding his two weeks leave.Thus the actor refrained from attending the party in order to avoid any further consequences.
A source says, "The reports stating the Maharashtra government is looking into his repeated furlough, completely freaked out Sanju. Sanju and his family feel his furlough may be cancelled. He has therefore decided to keep a completely low profile for the two weeks that he is out. Salman Khan was very keen to invite Sanju to his week-long birthday bash in Panvel. But considering the suspicion with which Sanju's furlough is being viewed, the Dutt family has decided that Sanju will stay home. Only selected friends would be allowed to visit."
Dutt family doesn't want the government authorities to cut down on Sanjay's leave period, as the actor wants to spend time with family, before he returns to jail.