Request Code Adobe Photoshop Elements 12 for Mac

My Dad purchased me a copy of Adobe Photoshop Elements 12 in 12/2013. Before I could install it, I moved and lost it.

I recently found it again. It has never been opened and has the receipt taped to the box. 

I am trying to install it on a 2013 Imac.

It gets to the screen to validate the serial number, but refuses to connect to the internet and advises me to do the off line registration.

So I try that. It takes me through some steps where I exchange my Redemption Code for a Serial Number, then to a screen to enter a "REQUEST CODE" and my serial number that I just obtained.

The "REQUEST CODE" line is blank. There is nothing in the documentation about a "REQUEST CODE" and when I push the "Generate Response Code" button. It simply says 'REQUEST CODE INVALID" Most likely because it is BLANK!!

I have been all over thse forums and keep seeing the same advice, which does not work at all.

Where do I get a "REQUEST CODE"??????????

Thank you.