Macbook showing 410GB as storage whereas it showed 494GB before, rest it shown as (free space) in terminal not a part of the main SSD

[The terminal shows I still have 512GB of space but only 410 is being used in the macbook, rest is classified as (free space). Image-[1]

The disk Utility doesn’t show the 84GB anywhere either, is any of the partitions, but the full disk still shows the 512GB. Image-[2]

How do I add this (free space) back to my main SSD?