pdf converter queue not responding

Hi, I uploaded a file to the converter 5 days ago (right after the prior conversion), and it has been "pending" since then. I was converting a longer PDF 1 page at a time, because I find the converter is more accurate. So I have page 1 of my song, but haven't gotten page 2 etc yet because the queue is stopped. (see screenshot).

Is anyone else encountering this? Suggestions for how to "unstick" it?
Thanks.