It is NOT a problem. Get your new passport. Somewhere in the NEW passport, there will be a mention of the OLD passport number. Fill up the RP renewal form with the NEW passport number. Go to any of the renewal centres with both passports. MoI staff will update their databank and issue the same RP with the new passport number on it. The validity of the RP shall remain the same as the earlier RP. As far as I remember, I was NOT charged for the change in passport. Hope this helps!