I am trying to get a serial # for my lax v2 as the one I have does not work,it's the same serial # from the original d/l I have tried several times to activate through the manager but I still get invalid serial
If you have a Serial from a previous email, Esellerate won't give you a different one so, unless you copied the original purchase receipt manually and made some error, getting a new identical purchase receipt won't change your issue with the serial "invalid".
If you could make a more precise report (there's no "invalid serial" message anywhere in the program, so you must have seen something different), we could help understanding what the problem is. For example, you might have seen an error about having used too many activation, and there's a solution for that. Or you might have seen an error about the serial belonging to a different product, usually because you selected the wrong product for activation.
Or, you might have seen an error about having mis-typed the serial number. If you are sure you typed it correctly, it's possible that, if you used Copy & Paste from the email, you might have not noticed you copied extra characters (even invisible ones), that will make the serial wrong, even if it "looks right" so, in this case, it might be best to type it manually.
Of course, if you saved your .REG file from a previous installation (it was automatically saved for you in the C:\Users\YOURNAME folder ), you could save all this manual serial number typing, and just double-click on the .REG file to include it in the registry, without having to type it manually.