As an outsider I can only offer you general advice. Please bear that in mind. I suggest you visit your former employer in Yinchuan to try to negotiate a settlement re the broken contract with him. Were that to be possible, you and he could then see the Yinchuan Waiban to ask them to arrange for your name to be taken off the black list. I'm sure said Waiban would ask the Beijing Waiban to do so, and I can't see any reason why the latter Waiban wouldn't acquiesce. I'd have thought the best way to get a positive result would be to go back to the person whose original actions have led to you having been blacklisted. If you think there's no chance of a change of heart by your former employer, you could try the Yinchuan Waiban. It's questionable whether you would get help from there, and even more questionable whether the Beijing Waiban would help you. In a word, go back to the source of the problem that led to the actions of both Waiban against you.