Not visible to opposite party while using Video Calls feature

Why the video is not visible sometimes to the opposite person on call with you? This issue is arising on Whatsapp, Facebook messenger, Goggle Meet applications, not sure why it happens at randomly?

I am sure it’s not just the issue with other apps but iOS 18 update on my iPhone 15.

Sometimes the opposite users have complained about the audio/video not audible/visible even though the feature is not disabled at our end (i.e. Video/Audio is off) which happens randomly. Please provide a fix on the next update.