Good Morning! I hereby inform you that my assembly has not yet started to run, as you are saying that it is still pendete to run. I would like to know if such an event is normal and how long it takes to start.
It is normal for jobs (any tool) to queue first, then execute.
The timing depends on the tool, how many jobs you have running, and how many other people are using the shared resources at the same public Galaxy server.
Allow queued jobs to remain queued. If you deleted and rerun, the new job is placed back at the end of the queue again, extending wait time. The exception is if you already know that there is a problem with the tool run and need to start over anyway.
I added a tag to your post that covers prior Q&A and FAQs about how jobs execute. Click on it to review if things are still not clear.