That’s correct @Anna. Your site is served over HTTPS and therefore resources called (e.g. scripts, stylesheets, images, etc.) need to use the same protocol otherwise you get errors such as this in the console
Mixed Content: The page at 'https://cardano-bean.netlify.app/' was loaded over HTTPS, but requested an insecure XMLHttpRequest endpoint 'http://159.89.188.76:3000/bean/redeem'. This request has been blocked; the content must be served over HTTPS.
The issue in your case then is that http://159.89.188.76:3000/ is not available over https (ie. https://159.89.188.76:3000) as it would appear it is not configured with SSL.