Seems to be a hot topic recently. I first discovered https://www.hoxhunt.com/, there are probably some other competitors as well, what makes you different?
I would be interesting in this answer as well. There is actually quite heave competition in this space: PhishMe, PhishLabs, IronScales, MediaPro, KnowBe4, Wombat (acquired by ProofPoint).
Not OP, but I will say, of those companies, only two or so really focus on this as the market is incredibly saturated. For example, Attack Simulator via Microsoft was recently announced, and their O365 brand is one of the most abused. Most have acquired other organizations to find higher ground.
What convinced YC to invest in your company?