For oinp/bc/sinp in graduate masters/phd or student stream, based on many previous posts from users and
spreadsheet, it appears that after one gets AoR, they get ADR with paystubs, company/employment letter, t4, pof, bank statements sched etc. (this could be in some cases, just to ensure if you're still employed / have enough funds)
While we don't know what exactly the letters say, it would be good of you can paste some of the details here, and masking personal info, to understand what exactly packages mean. My wild guess is that If they are asking for "package", it seems that your application is maybe incomplete or some files got corrupted who knows how they handle (if online based) and hence they ask for package or maybe you sent paper based and they lost your package partially or something.