Hi Sharmil,
After you downgraded back to 6.2.1, did you revert the changes you made to the Process for 6.6 back to 6.2.1 as well? I would think that using the original 6.2.1 Process should resolve the issue. BP provides Process history so you should be able to go back to the original 6.2.1 state and retry.
If you're still not able to resolve the issue, I would suggest logging a ticket with Support.
Thanks,
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Mohammed Ali
Head of Customer Support (Americas)
Blue Prism
Austin TX
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