I'm sorry to hear about the difficulties you have been experiencing. I reviewed the support case that you filed on this subject and, while I understand that you have been seeing incorrect listing counts on your My Plan Info page, we were never able to see that inaccurate information from our side of things.
I also did some further testing to see if I could reproduce the behavior you described, but I was unable to do so - even when checking the My Plan Info page immediately after the items I relisted were posted to eBay successfully.
Although it is difficult to tell exactly what may be causing you to see inaccurate information in this area is that, when you initiate a post or relist of an item, the item will actually be scheduled to post or relist immediately and it generally takes several seconds (sometimes longer) for the item to be submitted to eBay successfully.
As such, I am curious if you may be checking your My Plan Info page so soon after listing your items that all of them may not have successfully posted to eBay yet and therefore are not being taken into account by the remaining listing count on that page.
If an item you have requested to post or relist has not been posted yet, you should be able to see a record of that on the Scheduled Listings page within your account - a post or relist attempt that is still in progress will relect a status of “Posting” or “Processing” there.