Yes, it seems the SSD doesn't have a temperature sensor.
Please send me a screenshot of the Sensor Configure screen before and after restart, it might also be helpful to attach a registry dump of the following key (using regedit): HKEY_CURRENT_USER\Software\HWiNFO64
Also one question: this this problem occur also after you close and start HWiNFO64 again, or is a reboot required to reproduce it?
You might also try to "Reset Preferences" prior to HWiNFO start to see if this fixes the problem.
Definitively, that must be the reason.
Does the order of devices after reboot change in system and HWiNFO64 under Drives ?
Can you please attach the respective Debug Files with sensor data too?
Indeed, the debug files confirm, that the order of drives in system changes after reboot and that's the reason why your sensor settings in HWiNFO are applied to a different drive after reboot.
Since HWiNFO keeps the settings per device index, there's no easy fix for this. I'd rather search for the reason why this happens. Do you have an idea why?
That won't be easy, but I'll have a look at it.
Anyway, I think it's not ok when the order of drives changes between boots and that it should be fixed on operating system level.