Postback Issue in C#/Asp.net

I have a page where there user fills out information for an event. Well I have a reset Date button where I just want to reset the date/time area and not the top part where they put their company information in. I have some radio buttons on the Date/Time Area to let the user decide if they want to do a repeat pattern or not. Everything resets, but the radio button for Yes Or No to do a repeat pattern lose their post back function. If I hit F5, then it comes back. Is there a way to keep the post back etc in there even when just trying to reset that one area? I have the code below in my ResetDate button click, but that doesn't help.

rbRepeatNo.AutoPostBack = true; rbRepeatYes.AutoPostBack = true;
            rbRepeatNo.CheckedChanged += new EventHandler(rbRepeatNo_CheckedChanged);
            rbRepeatYes.CheckedChanged += new EventHandler(rbRepeatYes_CheckedChanged);