Resizing blog header image

How do I resize the header image so that it covers the entire mobile web page?
From the image I have attached you can see it leaves a white space before getting to the text of the page, I’d like the image to cover the mobile web version completely, THEN scroll down to the content.

Can someone provide me the coding and where would I put this coding to make those adjustments?

Hey there

Perhaps i can help you, but please provide link to the page

My website is


I hope you are doing well today.

For some reason the site is not loading, are you currently making changes to it?

Best Regards,

The website should be loading , its quite slow which is another problem i also have.

Hey there

Sorry, but there is no other way to change appearance of this image on the mobile screens, as i can see you already used all possible options in the customizer to set up this image. and image is also changed
Loading speed - image is 2mb, you must optimize it