Unable to change partition size and lesser free space shown in High Sierra Boot Camp

I have just deleted the local snapshots and free up some space. However, the partition slider isn't moving at all and stuck at 37 GB partition size. I am having approximately 55 GB of free space right now but Boot Camp is accumulating 45 GB of free space, which is still a 10 GB differences. Could this due to having too less free space left for my Mac partition disk or contiguous space issue?

The FAT partition disk also allows a maximum space of approximately 41 GB, which is the same space as the Boot Camp partition disk, 10GB lesser than the shown free space from Disk utility.

Hey, it seems that I was unable able to get the contiguous space back after erasing my internal disk from Recovery Mode and restoring the Time Machine backup, but I was able to get the space back after failing to partition FAT disk from Bootcamp and erasing the Bootcamp partition. The problem now is that the partition size slider in Bootcamp only stuck between 39GB and 37GB, and anything greater or lesser than that isn't allowed.

Moreover, an error occurred stating "The Windows support software could not be saved to the selected drive" during partitioning process, which eventually fail.

I will try to run First Aid in Disk Utility if I it would fix anything.

Currently, there are no local snapshots generated yet.

Ah my bad, but it seems that there is no output from the command and the local snapshots are probably empty.