Get a lawyer. You need to reopen or refile the motion/petition to terminate the guardianship and you need a letter from CPS that the case is closed with no need to follow or complete any case plan (as there is no active case plan). A lawyer will be better able to "convince" CPS to do what is needed, including issuing subpoenas for documents and witnesses as may be necessary. It sounds like the Judge did not believe you in 2012, but if you had brought a CPS worker as a witness to support your claims, you probably would have been okay. A lawyer can review the case history and court orders and make sure that this time you have everything you need to prove fitness to get back custody of your child.
Responses are for general information purposes only, and are based on the extremely limited facts given. A consultation with an attorney experienced in the area of law(s) indicated in the question is highly recommended. Information and advice given here should not be relied upon for any final action or decision, as the information is limited by its nature to the question asked and the fact(s) presented in that question. THIS RESPONSE DOES NOT CREATE AN ATTORNEY/CLIENT RELATIONSHIP, particularly considering that the names of the parties are unknown.
I could see where the DFS case might have been closed without you completing your requirements - for example, by way of a consent custody order (NRS 432B.550), or by making the guardianship "permanent" (nothing about guardianship is actually permanent). So the guardianship judge may be pointing out that objectively, you have not completed your CPS case plan requirements, and as such, have some work to do to terminate the guardianship. This is especially true if you objected to the guardianship and it was granted anyhow, which then extinguishes the "parental preference" and you have to show 1) a material change in the circumstances of the child or children; and 2) the child or children's welfare would be substantially enhanced by the termination of the guardianship (essentially the same standard used when trying to change custody from one parent having primary to either joint or primary custody the other way. In any event, it is clear, as you have been advised, that you need legal representation to walk you through this process...
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