I'm a little confused by your question. I believe you are saying that you need to reschedule your court date for AG court in Polk county, but when you attempt to contact the county clerk, they tell you to contact the AG court, and the AG court tells you to contact the county clerk?
If that is your case, then you need to file a motion for continuance. You file the motion for continuance with Polk County District Clerk, but you need to either fax or mail a copy of that motion to the AG attorney's name listed on the pleadings you have.
I strongly suggest you contact an attorney who can at least appear on your behalf to get the case rescheduled at the hearing if they are not willing to reschedule your court date and you are unsure if they will honor your motion for continuance. Without an attorney or yourself there personally, you could have an order entered which does not correctly reflect the facts, and you could wind up paying more child support than you should (because the AG court will be relying on someone else's evidence of your income) and your possession and access of your child could be severely limited (because again, the AG court is relying on someone else's evidence).
Normally, child support services (AG) would be the one to ask or request the continuance but the court is the one that needs to continue. I would recommend that you get a hold of AG to make sure that they are fine with continuing the case. If so, ask if AG will appear and continue the case.