Cell phone problem? - 1

I realized yesterday that when I record videos and then want to watch them I only hear the sound and the rest is just black. Why is that otherwise it always worked and today I tried it again, it's still like yesterday. I have a huawei cell phone with Android.

Do you have a protective cover on the lens or the cover covers it? Otherwise, call the dealer where you bought your cell phone.

The case doesn't cover anything