Follow these steps to check what might be wrong and if this doesn't help, please do get in touch.
Here's some simple things to check that we've seen before:
Check there aren't any 'empty' spaces before or after the code. If you've copied it from an email for example it could be that an empty space has been copied before or after the code. Please delete any spaces.
Please check between 0 (the number) and O (the letter). This is another one we have seen before.
Please check with your coach that the code can be used on that program.
Please check with your coach that the code is still active.
If that all seems correct, please do get in contact. We will need:
The code you're trying to use
A link to the program you're trying to use it on.
This is so we can recreate the error you're seeing.
Thanks
FITR