how to fix duplicate posts after blogger importer

Hi,
I used the Blogger importer to import my posts about a month ago. I was continuing to publish on my old site and ran the importer again.

Now I have duplicate posts.

It says this won’t happen on the plug-in…. so that’s a bummer.

But mostly I’m interested in fixing this as quickly as possible.

I need to know the easiest, most effective way to fix the problem.

Is it best to delete all the posts and reimport?

Is there some way to automatically delete dupes?

I have a back-up before the latest import I can revert to if that would help.

Thanks,
Stacy
https://sweetsky.net