You're a PM at Booking.com. A sales manager reports that the app is returning a 404 error. How would you investigate the issue?

My first step would be to reproduce the 404 error reported by the sales manager to pinpoint the exact page or feature experiencing the issue. Simultaneously, I'd investigate the impact by checking the user base and metrics associated with the affected flow to gauge its criticality. I would then collaborate with the engineering team, sharing all gathered information, to diagnose the root cause and establish a prioritized timeline for a fix. Communication with the sales team would be ongoing to keep them informed of the progress.