Minor child passport application

My minor child passport application status is showing as "Passport application is put on hold at RPO due to following reasons.
-Additonal documents upload
your application is under review at Passport office .Please visit passport office only if you are called to do so through letter or email.
Can anyone suggest me what needs to be done here because I saw application status few days back was showing as police verification initiated.I am not understanding what is the issue here.