This could be a security problem. Did you import the certificates?
Is this an https request?
The documentation about certificates can be found here: https://docs.mendix.com/developerportal/deploy/certificates
But the only one who knowes if certificates are used on this webservice is you. Might also be that your IP is blocked. Then contact the webservice provider to add your IP to the range.
Have you set the proxy settings in the call rest action?
Please find the settings.
Please find the attachment which contains settings for Proxy in REST Call, this is test app. It is also not working Run locally.
That does look like a proxy problem. Have you read this page? https://docs.mendix.com/refguide/using-a-proxy-to-call-a-rest-service
Make sure you have
http.proxyUser , and
http.proxyPassword all set with the values for your network in your Mendix Project Settings, Configuration, Custom tab.