WIndows 10 shrinking a SSD partition

[ssal]

I have a 500 gb SSD for boot. File explorer said 350gb is free. But when I went into disk management trying to shrink it to 250gb so I can create a drive D in the new volume, it said I can only shrink 36gb.

How can I free up the space so I can shrink it more?

 

[johnb35]

Use minitool for partitioning.

https://www.partitionwizard.com/free-partition-manager.html

 

[ssal]

Use minitool for partitioning.

https://www.partitionwizard.com/free-partition-manager.html

That exactly what I found in browsing. And I have just resized the OS boot drive to 175gb and increase the D drive to take up all the space.
Thanks.