Some aggressive antivirus suites include "Webcam Protection" tools designed to block hackers. However, these tools frequently block legitimate applications by mistake.
Open your video app's settings menu, find the video tab, and ensure "Intitle X5" or "USB Camera" is selected instead of your laptop's integrated webcam. intitle webcam x5 work
Aggressive security software can lock down your webcam to protect you from spyware, inadvertently blocking legitimate video calls. find the video tab