2013 Honda Civic Si

My car sometimes doesn’t turn on. But I can jump start it right away and it will work for a week then it won’t turn on again. I’ve gotten both my battery and alternator checked but they are both good. Could it be a tune up? Or what could it be?

change the battery terminals, they may be corroded inside. IF the battery has been tested and it's actually good, it's either that or a short draining the battery over time. Try this video for finding battery drain https://www.youtube.com/watch?v=B__DqK90IIc