For you, a relatively simple method is:
Purchase a USB adapter that can recognize M.2 SSDs, or use the M.2 port on your PC (if your PC has multiple M.2 ports)
Delete the volumes and storage pool of two M.2 SSDs (backup data if available)
Turn off TNAS and remove one M.2 SSD (M.2 SSDs do not support hot swapping, and the M.2 interface on PCs is also the same.)
Connect the extracted M.2 SSD to the PC and delete the volumes/partitions of the M.2 SSD through disk management tools.
A relatively difficult method is:
If you know how to use Linux commands, please log in to SSH or execute the following commands with super administrator privileges through custom scheduled tasks.
You you want to use this method, please enter this commands to and copy the output here so we can see the structure of your storage and tell you how to do next.
To contact our team, please send email to following addresses, remember to replace (at) with @:
Technical team: support(at)terra-master.com (for technical support)
Service team: service(at)terra-master.com (for purchasing, return, replacement, RMA service)