Made a mistake on CV- What to do?

I've applied for a grad scheme and had just finished taking the aptitude test when I got a chance to go through my application. I noticed in the CV I attached that I got one of my employment histories wrong. I wrote July twice. I wrote July 2021 to July 2022, when it should have been July to February. I was sick with Covid at the time I was applying and my mind was somewhat hazy. What should I do? Should I contact HR? Will this somehow ruin my chances?