There are strict time limits for a party to challenge a judge based on CCP 170.6. If you missed those time limits, or the judge has done anything of a material nature in the case,then you cannot use a 170.6 challenge.
You might be able to file a motion to disqualify the judge for some other reason, but you will have to show cause. Look at CCP 170.1 and the statutes following it to see if maybe one or more reasons stated there applies to your case.
Don't even try to disqualify your judge unless you are darned sure your effort will be successful. That means you need a professional evaluation of your basis. Less than 1% of efforts to dq a judge (after the short window for peremptory challenge has closed) will be successful. Maybe less than .1%. It's that hard. There is nothing worse than being stuck in front of a judge that you tried and failed to remove.
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