Make sure that the order specified you would get a percentage of the bonus. If that was the case he is in contempt for not paying it. You need to take him back to court to encorce the order.
You need to find out how exactly how much the other party actually earned, and may need to do some discovery to obtain back pay records, pay stubs, tax returns, etc. You could request an updated Income & Expense Declaration, but I don't think will give you enough detail.
You may find out that you are owed a lot of money, but you may also find out that the other party's income has been lower than expected over the past two years (given the state of our economy) and that no additional support is owing.
Was your support being enforced by a wage assignment order? If so, the employer should have been keeping an eye on this very issue. If not, then you should consider getting such an order at this point. In any event, a consultation with a family law attorney will help you to answer this question. Best of luck to you.
This response is intended to be a general statement of law, should not be relied upon as legal advice and does not create an attorney/client relationship.
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