What happened to my original account?

I just had to re-join this forum that I had registered for a few years ago. I haven't been using my Davinci Studio for a couple years. I can use the Davinci Resolve on my old iMac but cannot open it on my MacBook Pro, which I have been using it on ever since I bought Davinci Studio with the Speed Editor. Now I'm being asked for my license activation number in order to open the app! I have no idea where this is as I've been using the program for years.
Please help!

Thank you and I apologize for my panic. I hadn't used my Studio for a while but I had saved my card with my activation number so I'm all set. Still not sure why my Forum account password didn't work. Probavly the same reason, lack of activity? Anyway, all good now.