Thanks everyone for your suggestions. Well I think it could be the problem with the "Open Path" because the illustration was super-detailed with 1000's of layers, so I re-checked my illustration and it contained almost "426-Open Paths" which I selected manually 1-by-1 to close each and every single path so there were "0-Open Paths" left then I re-packed the logo and uploaded once again and it worked. I'm sharing that experience with everyone and I hope that might help someone if in-case he/she stuck in the middle of uploading these type of super-detailed or busy logos/illustrations. I hope that helped.
OR
Maybe it would be you Alex, who helped me in that case to resolve that technical issue(bug/error) so finally the files have been uploaded and now everything worked perfectly and the issue has been resolved.
Anyways, thanks a lot for all your help guys, much appreciated your quick action/response for helping me with that issue. TC all.
Thanks!
Best Regards,
Immo0~