Yarn - There appears to be trouble with your network connection. Retrying
This happens when your network is too slow or the package being installed is too large, and Yarn just assumes it's a network problem. Try increasing Yarn network timeout:
yarn add <yourPackage> --network-timeout 100000
Deleting the yarn.lock file and rerunning "yarn install" worked for me.
I got this issue because I was working within my company internal network and proxy needed to be set.
$ yarn config set proxy http://my_company_proxy_url:port
$ yarn config set https-proxy http://localhost:3128
example $ yarn config set https-proxy http://proxy.abc.com:8080