Why do I see field names instead of the address when I design envelopes?

I’m running Win 7 and LibreOffice I’ve created an address database using the Base Database option in LibreOffice. When I open a new blank document and select Insert>Envelope the envelope template comes up. I select the proper database and table and then select the needed address database fields and enter them into the addressee field sequentially using the large, left pointing arrow. The field names appear on the envelope template. When I print the envelope the desired address data does not appear but just the field names (literally as typed below)

 <First Name><Last Name>
 <Post Code> <City>

Any idea what I am doing wrong? The same thing happens on my Linux box so there is clearly something I’m missing. Thanks in advance for your help.

I’m on Linux so maybe it’s different but…
I followed the steps as you listed, and chose to insert the envelope into the document rather than to create a new file.
When I hit the print icon or choose File > Print I get a dialogue “Your document contains address database fields. Do you want to print a form letter?” I hit yes and then I get the option to choose the records from my database to print. I"m assuming you don’t get the dialogue asking if you want to print a form letter?

Please test the options:

Menu/View/Field names [Ctr+F9]

Menu/Tools/Options/LIbreOffice writer/View - Display - Field codes.