I bought vegas edit 365 and was sent activation codes for BCC Fx, specifically (Boris FX BCC Optical Diffusion 2021.5 Unit)

I am currently trying to use the code that was given to me and it says it has already been used before. Which it has been, but only on an older version of vegas that was on the same pc that I am currently using. Anyway to get a new code or to somehow find and deactivate the older one? I need help with this cause I am being limited on what I can edit due to the fact that I can't access BCC Fx