Does it just say likely? No. It says very likely, like It's very likely you haven't actually looked up the word likely in a thesaurus or for that matter a dictionary.
having a high probability of occurring or being true : very probable
Add a very and that's very very probable.
Now onto "sure"
marked by or given to feelings of confident certainty
Yeah that's very likely to help you figure out where you went wrong.
See how I didn't say it was definitely going to help? Because even though most people are capable of figuring out such a mistake, I can't see into the future?