Episodes listed as season 2 are actually season 3 and the whole true season 2 is missing. How can I correct ? This means to renum current season 2 to 5 as seasons 3 to 6 and change initial date for "new season 3 (current 2)"
So there were 6 seasons of this series, not 5. From what you described, the episode numbers will need to be corrected before adding the missing episodes for season 2. The submissions will need to be corrected in stages. You'll need to wait for the updates to be processed before correcting the show's other seasons.
Start with the season 5 episodes. The episode numbers will need to be corrected to season 6. (Change #5.1 to #6.1, change #5.2 to #6.2, etc.).
After all of those episodes have been processed and published, start another correction for season 4 episodes. (Change #4.1 to #5.1, change #4.2 to #5.2, etc.)
These are the same instructions for the other two seasons as well.
After all of the corrections have been processed, you can add the missing season 2 episodes to the title.
I hope this helps. Please write back if you need some assistance.