Maybe I have not explained well or I did not understand how.
Attached a screenshot of my panel Invoice configuration, where I find the Numbering configuration?

thank you

Ok these are bugs, but now how can I change the prefix of the invoice from 11 - to 12 -?

Hi, when I press the save button I get this error message:
"Wrong datatype for second argument..."

The configuration is saved, but some options are reset themselves.

Also in the user guide I found a section that describes "invoice numbering," but I do not see in administration these options , why?

thanks