Hi guys
we are moving from RTC to Jira and we used the Epic->Story->Task hierarchy and I know that now we have to change our mind and start thinking to Epic ->Story->Sub-Task.
My exported RTC workitems in CSV have the following structure:
Type Id Summary Description Parent ID Epic ID Status Priority Severity ... (I have 55 columns in my csv)
Obviously, ID is an unique identifier in CSV (and also in my RTC system).
This could be an example of my CSV:
Type Id Parent ID Epic ID ...
Epic 1
Story 2 1
Task 3 2
Task 4 2
Defect 5
I try importing my CSV using this map options:
ID -> Issue ID (sub-task field)
Parent ID -> Parent ID (sub-task field)
Type -> Issue Type (issue field) mapping Task to SubTask IssueType
At this moment, relationship between Epic and Story is not my priority (but if someone have any idea to solve also this issue

)
But no parent-child relationship is created in Jira....Where am I wrong?
Additional Info:
Jira version: 7.2.3
CSV size: > 80Mb (I have increased the attachment file limit to 100 Mb)