zelt does not propagate errors

[Olamyy]

Describe the bug
When a command related error happens, zelt doesn't show the error. It just shows the help message. I understand the help message should show the correct commands but it doesn't exactly tell what the error is. It'll be great to have some error message that points to what the error is.

Zelt version
Output of the command zelt --version.
1.2.15

To Reproduce
Steps and input files to reproduce the behavior:
2. Run : zelt --thisisaninvalidargument
3. See error

Expected behavior
There should be an error. Something like "thisisaninvalidargument is not a valid argument"

Screenshots
If applicable, add screenshots to help explain your problem.