Drupal 6 to Drupal 8. Forum problems after migration.

After much pulling of hair and screaming I think I have manged to migrate most of my content from D6 to D8.

My Forum content seems to have migrated, however I am faced with the following problems that I am looking for some help with.

Only one Forum Topic is listed ie: General Discussion

Although all forum posts seemed to be have been copied only one forum topic was created and it had no forum posts in it. The link to screenshot below shows one post.

https://s3-us-west-1.amazonaws.com/drupal6-to-drupal8/Images/2017-06-29_…

This is because I manually opened the post and assigned it to that Forum Topic as shown at following link

https://s3-us-west-1.amazonaws.com/drupal6-to-drupal8/Images/forum.png

The nightmare fix would be to make new Forum Topics and then re-apply the posts one by one to the respective Forum Topic which is obviously not a practical solution. I am looking for another way to fix this.

Comments copied but no Subject

As seen by the following link to a screenshot. Comments have been copied across but there are 2 problems.

1. The comments are not tied to a subject
2. The author is listed as “anonymous_stub (not verified)”

https://s3-us-west-1.amazonaws.com/drupal6-to-drupal8/Images/2017-06-29_…

I am looking for some help with this also.

Drupal version: 


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