global variable not always global

I am relatively new to Matlab. Sometimes when I declare a variable as global its value does not carry to all functions. I list the variable in the 'global' section at the top of each function. I see the variable in the global section of each function, but the code does not see it that way. When I highlight that variable all other instances of it are highlighted in the function. But the same variable is not highlighted in other functions. It is not incorrect spelling or capitalization - I have copied and pasted. I know I have sometimes I declared a variable global more than once in a function and then deleted the duplicates.

My question is once I've made this mess how do I correct it so the code works.

Thanks for your help with the elementary question.

Jim

[the cyclist]

It is difficult to diagnose this situation without seeing any code. Are you able to provide an example that illustrates the problem you are having?

[TAB]

It will be better if you can share the section of your code.

[Walter Roberson]

I would not expect the MATLAB editor to highlight copies of the variable in other functions.