usually problems like this depends on the URL you are trying to access and from where you try to access them.
Some possible issues can be:
- HTTP vs HTTPS
- reachable addresses (e.g. if you created widgets with "localhost")
I can not see the effective request to GeoServer so I can only think about some possible reasons. One possibility is that you created the widgets using a URL like "http://localhost:8080/geoserver/
" or something similar, and then you are trying to access it from a different IP the browser blocks the request or the firewall do not expose GeoServer on that IP.
In general if you are not able to inspect these kind of problems, I can suggest you to create the widgets with the effective address you will use.
Otherwise I suggest to see the reason opening the developers tool to get the effective error.