There's nothing to fix.
It's just two different units of measurement. Drive uses GB (multiples of 1000) , Windows uses GiB (multiples of 1024)
It's advertised as 1 GB = 1.000.000.000 bytes .
Windows uses multiple of 1024 meaning 1 GiB = 1024x1024x1024 = 1,073,741,824 bytes
So 500.000.000.000 bytes / 1.073.741.824 bytes= 465.66 GIB
You actually have 512 GIB or even more memory in the ssd, but that difference of around 50 GiB is hidden from you and used as spare memory (replaces memory that goes bad from heavy use over time so it extends the life of your drive ) and to cache writes to increase write speeds,