Hello Uday,
I also witnessed the same issue.
In my case, I found that parameter 'SAP-WD-RESUMEURL' is not actually returned thus navigation was not working. Also, I suppose that this parameter is not returned while navigating through portal.
What I did, instead of using suspend/resume functionality, I'm navigating again on BACK.
Hope this helps.
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Best Regards
Jitin Kharbanda