`smartctl` and `smartd` commands not working

I have been receiving hard disk warnings from the smartd daemon for a while now (every 24 hours), saying that my error logs have increased. I have been trying to examine this by checking my log files, but I haven't found anything. The error logs are for my hard disk /dev/nvme0. I've been trying to find out what this problem is and have been trying to scan my hard disk using smartctl or smartd command, but I keep getting back command not found. I have the packages installed and I even can open the manual pages; man smartctl and man smartd. How can I resolve this issue? The warning I receive is the following: