MacOS Unable to use “(free space)” in BigSur
You can not add free space that resides above a APFS container. An alternative, outlined in this answer, will not work because the APFS container is to large to be cloned to the free space you wished to add. You would need to first reduce the size of the Vaats - Data⁩ volume before applying the answer.
You could try shrinking the current APFS container and to create a new temporary partition. Move files from the APFS volume ⁨Vaats - Data⁩ to a volume in this new temporary partition. The idea would be to reduce space occupied by data in the APFS container so the APFS container could be cloned to a new APFS container you would create in the (free space). After cloning, the original APFS container be removed and the new APFS container could be expanded to reclaim the space. Next, copy the files stored in the temporary partition to the cloned APFS volume ⁨Vaats - Data⁩. Finally, remove the temporary partition and expand the new APFS container to reclaim the space.