message box in not working

In the following simple code, the message box is not working:

prompt={'Enter the first number:','Enter the second number:'};
dlg_title='Data Input';
num_lines=1;
n=inputdlg(prompt,dlg_title,num_lines)
N1=str2num(n{1});N2=str2num(n{2})
c=N1+N2
message=num2str(c)
title='The sum'
msgbox(message,title,'error')

I have got the following error message

Index exceeds matrix dimensions.
Error in InOutBox (line 9)
msgbox(message,title,'error')

Answer 1

[Guillaume]

Possibly, you have a variable in your workspace called msgbox. What does

which msgbox

returns?

Note that you may run into the same problem with your title variable if you try to use the title function.

[Abdallah Shaltout]

Thanks Guillaume. Now it works.