Hi Husna,
Which version of DSpace are you using?
You might have already seen this, but there is a wiki page on the use of SAF Packager. Due to a lack of maintenance, SAF Packager has become outdated, which could be part of the issue you are describing (depending on your DSpace version). There are several other recommended alternatives listed on this page:
https://wiki.lyrasis.org/display/DSArchive/Simple+Archive+Format+Packager
I hope this points you in the right direction. Please feel free to reply in case it doesn't. We can do some additional digging and someone else might have additional feedback pertaining to your question.
Holger