SSD Plus 240GB Total NAND Writes keep increasing without any disk activity

I have a SSD Plus 240GB, and its Total NAND Writes increases about 50GB per day, without any disk activity.(See Attachment)

The disk is only 20GB used. I can’t figure it out. Please help.

Install the sandisk ssd dashboard and check to see if a FW update is available. 

https://kb.sandisk.com/app/answers/detail/a_id/15108 

It’s been installed, and no update avaiable.

in that case i would recomend contacting sandisk support.