Post Featured Image not Resizing

My featured images on my blog posts are not resizing and are being cut off when you click to open the post. The thumbnail for the post looks great, but when you open it the image isnt resizing. I have even installed Imsanity plugin to help and try to auto resize pictures, but still no luck. This has been an issue for a while, and I am no coder. Can you take a look? Its no problem on other websites I have with different themes so I have narrowed it down to the theme.
I attached a picture.

I have another issue, but its very small and quick. Am I able to change the author of a post to a different user even though I am the one who is publishing the post?
Thank You

-Mike

Hey @beanmr,
Hope you’re doing well today

Sorry about the issues you’ve been having here. Could you please try using the Force Regen. Thumbnails plugin and see if that helps?

Check it out here: Force Regenerate Thumbnails – WordPress plugin | WordPress.org

I hope this helps :slight_smile:

Best Regards,
Support