Wavelab 6 serial number

My Wavelab 6 will not show its track list in the main editing window, so I want to reinstall to try to correct the malfunction.
When I try to reinstall there is a challenge to enter the serial number.
I don’t know where it is.
I checked all the info relating to my eLincenser on my system and online and it seems there is no relevant info there.
Does anyone one know where I can find it?

Thanks in advance.