NPM-install error for upgrading ng-uikit-pro-standard-6.2.5-

1. Downloaded the latest version  --   ng-uikit-pro-standard-6.2.5-npm
2. Then generated a token and replaced it inside package.json as per the instruction given
3. Then run the npm i and it gives error
4. Set the http proxy correctly, still not able to figure out what is the issue is

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX D:\ng-uikit-pro-standard-6.2.5-npm>npm install npm ERR! Error while executing: npm ERR! C:\Program Files\Git\cmd\git.EXE ls-remote -h -t https://oauth2:TOKEN@git.mdbootstrap.com/mdb/angular/ng-uikit-pro-standard.git npm ERR! npm ERR! fatal: unable to access 'https://oauth2:TOKEN@git.mdbootstrap.com/mdb/angular/ng-uikit-pro-standard.git/': OpenSSL SSL_connect: SSL_ERROR_SYSCALL in connection to git.mdbootstrap.com:443 npm ERR! npm ERR! exited with error code: 128 npm ERR! A complete log of this run can be found in: npm ERR! C:\Users\ranara\AppData\Roaming\npm-cache\_logs\2018-10-11T04_50_48_938Z-debug.log      

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