onchange dropdown margins of text box get chaged how to fix?

Question

I have three drop down onchage event I have changing label value. Eg if drop down value is Courier Address

 

$("#lblAddress").html("Courier Address");

 

If drop address the

 

$("#lblAddress").html("Drop Address");

 

by default it is address

 

but alignment for below textbox and position get changed on each of dropdown selection.

 

How to fix div and td margins permanently it should not change after drop down value gets changed.