I find a few of developers are asking for jobs just to ensure other people don't get jobs.
After getting jobs they don't bother to reply or submit any specifications.
I think such developers should be blacklisted.
Also there is no procedure written in the rules on how to get back the refund.
Moderator, please advise on how to get the refund when the job has not progressed at all and after acceptance no attempt has been made by the coder to submit prototype or respond to queries.
Of course not, you have no idea why someone is not answering. Report it to ServiceDesk if you want (or arbitration, see above).
If the job is in progress (agreement has been found and accepted "Negotiation of requirements" step), they we can ask for arbitrage. Click the link and wait moderator answer.
Otherwise just forget it and select an other programmer.