Model MU-PA1T0B
I have a Portable SSD T5 1 TB. It has reached 985GB full, so I decided to delete a bunch of files that I didn't need. After deleting the unnecessary files, I decided to eject the ssd drive, unplug it, plug it back and what i see is still the same storage capacity with it being 985GB full (15GB left). I feel like this is a common issue with people or is it just me? Let me know if you can help!
Im not sure if this is the solution but I think the delted files might be sitting in your trash. Go to the Files app then go to trash to delete it permenantly. U can also disbable trash by clicking on the top right 3 vertical dots then turn off trash if it becomes a nuisance. 
