A few days ago I purchased the L3 Software Media (LE) update and loaded it into my system. Since then I've been getting repeated requests to submit my serial number for L4!? See below:

I'm confused on a couple of points, first of all in the past all one had to do was click the "next" button and the software would synch and that would be all there was to it. Doing that now doesn't resolve the issue. Everytime I open L3 I get the little tip window pointing me to the account management page to enter serial numbers.
Secondly, this is L3 why is it asking for an L4 serial number? Thirdly, when I upgraded to L4 Platinum from L3 all I got was a download so I don't really have a serial number, maybe more accurately I don't know what to put in the serial number box.
Thus my dilemma. What do I do?