If there is an answer there cannot be a default unless it was a cross complaint.
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Since there was a demurrer and now an answer, then no, default cannot be entered. I suspect there was a problem with the original default, because if it was entered, the demurrer and answer would never have been allowed. At this point, you are probably stuck litigating the case.
You might want to consult with a local lawyer who can review all the documents to be sure.