Huawei p20 lite holes in the shell?

I bought a case for my Huawei p20 lite and it has two holes on the right side down. But behind these holes there's no speaker or similar.

Is normal that a cover has holes… For fingerprint sensor, camera, headphone jack, etc…

But behind these holes is nothing the speaker is down, the fingerprint sensor and the camera at the back and the volume and standby button on the side above it