Welcome to Atlassian Community.
I understand that you are trying to import your Trello Board to a Next-gen project on JIRA, is that correct?
Unfortunately, this can not be accomplished directly, however, there are two ways you can do this:
The first one:
The second one:
Let me know if this information helps.
When to use CSV importer When managing your processes in Jira, there are many occasions where you need to create a lot of tasks. Creating them one by one will cost you a lot of time and effort and i...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events