There is no form to force him to continue paying. You will have to take steps to enforce the judgment. You can try and get a bank levy, a wage garnishment, bring him in for a judgment debtor exam. There are forms for those enforcement methods available online.
You don't say if this was a regular judgment (after hearing) or a mediated/stipulated outcome. If it was stipulated you will have to get a judgment before you can attempt to collect, which slows the process down.
There are a number if website which can help you with this effort. My favorite is the one below. Collection is difficult UNLESS you kept a copy of a check-- if you did, you can levy in the bank account fairly easily. It is SLOW, so be patient.
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