How to proxy ios dependencies which are stored in gitlab via nexus proxy

we are working on ios project and we have kept our internal libraries in our private gitlab . Instead of directly pulling those libraries from gitlab we want to proxy it via nexus. I have created a proxy repository in nexus and added that nexus proxy url in podfile of cocoapods but it was not able to pickup. Any suggestions.

getting error as----> [!] CDN: 1-repository-cocoapods-proxy URL couldn’t be downloaded: http://172.17.1.12:8081/repository/cocoapods-proxy/