Legal Question in Civil Litigation in California

It sounds like there's a judgment against you and they're seeking recovery of costs involved in litigation. If you want to challenge those costs, you would have to prepare from scratch a motion to tax (or strike) costs, file it with the court and serve it on the plaintiff's attorney.

There is no specific form. You have to file a motion to tax costs. The deadline is 15 days from service of the memorandum of costs. "Any notice of motion to strike or to tax costs must be served and filed 15 days after service of the cost memorandum. If the cost memorandum was served by mail, the period is extended as provided in Code of Civil Procedure section 1013." (Cal. Rules of Court, rule 3.1700 subd. (b)(1).)