Did you not see that those commands were examples?
The second example was to illustrate that the same can be done when performing an update; the update will complete and also write the command output to the text file.
Look in your ~/ directory; the files should be there.
1. When using those command examples from the Manjaro Live terminal the files cannot be written to the Live environment’s ~/ directory as it’s read-only.
2. You should have verified that my command was correct – as it turns out I’d made a clumsy typo (apologies, now corrected) and you blindly copied/pasted the example. That was guaranteed not to work. 
Later, you might be asked to enter a chroot environment to perform some maintenance, but the blkid output is displaying the expected information for now.
It looks like you’re missing much of the output.
Nevermind; this might not be neeeded (and remember, the commands were only examples).
From this point, you might have some success with the following Tutorial;
Note: The tutorial also contains instructions for those using a BTRFS filesystem – this is not you – please be extremely careful with that tutorial and do not blindly copy/paste commands that are not specifically needed for your system; 
It’s a tutorial, not a list of step-by-step instructions.
If this fails to bring any joy, one of the few remaining options will be a complete reinstallation of Manjaro.
Regards.