jquery modal opens to full page

Question

I have a nested jquery modals Modal1 & modal2 both contain updatePanels. To update the panels I am using javascript:

var prm = Sys.WebForms.PageRequestManager.getInstance();
prm._doPostBack('UpDateLookUp','');

UpDateLookUp is the id of the updatePanel for modal1. Modal1 contains the link, which is in the updatePanel, for modal2. Modal1 updatePanel is a search criteria(Find) outside of the panel which works great while I am on modal1 but when I open modal2 (has an wpdatePaneltoo) and I go back to modal1, select Find modal2 opens to full page and displays the info before it was closed & returned to modal1. If I click on the link that opened modal2 all is well it only occurs when I select a different button.

I am new to jquery so please help. this is the way our shop is going.