How is the title to the house held now? If the house is in your name, then you can file an unlawful detainer action, after providing the appropriate notice. If the title is not in your name, you’ll need to return to court and ask for an order, as well as amending/adding to your judgment regarding possession of the house. Although the default probably seemed like an easy divorce, this is an example of why it is a good idea to get some legal help with dissolution, even if you don’t expect to fight. You can ask an attorney for help now as well.
Best of luck to you.
This response is intended to be a general statement of law, should not be relied upon as legal advice, does not create an attorney/client relationship and does not create a right to continuing email exchanges.