cf  "Click here if you don't see  Choose file  and  Send File buttons."

Assuming you chose to upload or re-use a station file.

Recommended:
1
Wait. Repeatedly check the queue page for three to five minutes.
The job has probably been submitted without further notice.
If it appears in the list of completed jobs, examine the results sent to your email address.
Did you press the  Use File button? Next time, avoid it; use Send File instead.

2
Next time the same issue,
Navigate back to the Form page titled Create Request.
Check the selected parameters. Verify that they are what you want.
Remove all text from the Station window.
Press the  Submit  button.

3
If the problem re-appears, re-enter your request as a new request at the entry page.
You will receive a new token. 
Remove all text from the Station window.

4
If this does not help, send a mail to hgs at chalmers.se and summarize your observations.
Screen clips will be helpful for me to track down the bug.
 

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