If you copy your replays to your blog in order to clear a space for some new ones, then you need to delete them in a certain way from the replays section on your profile page.
UNDER NO CIRCUMSTANCES USE THE
REPLAYS SECTION DELETE BUTTON!
If you do use the delete button then they will be gone forever and any copies will not work anymore, which you have unfortunately just discovered.
Here is a video to show you how to delete them so that you don't void any links you've made that point to that particular replay & I'm sorry that you lost some good replays Bill.
VIDEO 1As far as I'm aware, replays last many years, maybe indefinitely, I haven't had one disappear yet for no reason.
For future reference, it might be better to share any good shots directly to your blog and skip saving them to the replays section on your profile page altogether.
VIDEO 2