My character encoding changes when I call a function from a guide

I am running a command that displays a message box from a user interface GUIDE. The problem is that when I run it from the command window it is display perfectly in its correct encoding format 'UTF-8'. But when it is run from Guide it displays it in another one.

h=msgbox('Por favor espere. Iniciando conexión','Instructions','modal');
cd('C:\Users\z_tja\OneDrive\LEGO MYO')

I set the default character encoding to UTF-8,

feature('DefaultCharacterSet','UTF8')

but it sometimes change again to ASCII.

currentCharacterEncoding = slCharacterEncoding()