URGENT : Visitor Visa extension denied for wrong reason

[CSC_EB3_GUY]

My in-laws have come to usa around January end.
Their I-94 was valid for 6 months until July 13th.

We applied for extension of their Visa on June 24th for 2 months until september 13th.

We received a letter on august 1st that states that

Contents of the Letter:
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The applicant's authorized stay expired on july 13, 2009. Review of U.S. citizenship and immigration services (uscis) records show that the applicants departed the United states on june 24, 2009, prior to the applicants initial authorized stay. Hence, the applicants' departure from the united states within their authorized period of admission constitutes an abandonment of their authorized non-immigrant status. As a result, the approval of this application serves no purpose. Therefore, the application is denied.

They are still staying here with us and its strange that their records show that way. I decided to contact USCIS regarding this and let them know.

But, I need help regarding how easily to approach them and what should I do further?

I sincerely appreciate your help.

thanks,
Venkat

 

[Triple Citizen]

What form did you submit and where did you send it?

But, I need help regarding how easily to approach them and what should I do further?