Hello @zareer,
First of all thank you very much for using the theme.
When we tested the theme locally, we were unable to find such kind of issue. The slider in every section is working fine.
So please make sure you have enabled the slider properly and added the image in the featured Image section of the individual post as the image in the slider displays from there.
Screenshot:
https://prnt.sc/k9q2ks
If the issues still persist even after this then please post your site URL so that we can look further into the issue and help you.
Thank you.
Best Regards!!