Without knowing what is in the building blocks it is difficult to advise, but you should not be using legacy form fields which require the form to be locked and content controls which don't. You should change the form field for a content control - see attached and also
Insert Content Control Add-In
Then you run the code on exit from the content control, which in the example inserts one of three autotext entries saved in the template according to the selection. Make your selection and click outside the control. Note you have five selections in your list but only three options in your code.
Create a new document from the template. The building blocks in the example insert a table with text at the end of the document or change that table if one of the three options is selected (or remove it if one of the others is selected).
This should point the way.