Background non secure when using HTTPS

Hello,

I have secured my website with a https certificate.
But i still have no padlock appear.

I have found out that this is due to some content that is not secure, it is the background of the main index page.

How can i fix this?

whynopadlock.com export:
Total number of items: 63
Number of insecure items: 2
Insecure URL: http://wolfsecurity.be/wp-content/uploads/2017/08/AchtergrondJ.jpg (background image)
Found in: https://wolfsecurity.be/

If i use no background, then the padlock appears.

Hello there,

I hope you are doing well today.

I have checked the page and I can see the padlock in the URL with the background. Please clear your browser cache and then clear the WordPress cache with the following plugin:

Best Regards,
Support