Getting npm ERR! git@github.com: Permission denied (publickey) when using deploy App

I am trying to deploy a React app using the digital ocean tutorial https://www.digitalocean.com/community/tutorials/how-to-deploy-a-react-application-to-digitalocean-app-platform

The tutorial uses the steps Create > Apps but deployment fails due to the following ERR in the log

2022-02-22T05:57:33.819281174Z npm ERR! Error while executing:
2022-02-22T05:57:33.819464259Z npm ERR! /usr/bin/git ls-remote -h -t ssh://git@github.com/ethereumjs/ethereumjs-abi.git
2022-02-22T05:57:33.819776780Z npm ERR! 
2022-02-22T05:57:33.820269927Z npm ERR! Warning: Permanently added the RSA host key for IP address '140.82.121.4' to the list of known hosts.
2022-02-22T05:57:33.820583459Z npm ERR! git@github.com: Permission denied (publickey).
2022-02-22T05:57:33.820899093Z npm ERR! fatal: Could not read from remote repository.
2022-02-22T05:57:33.821175028Z npm ERR! 
2022-02-22T05:57:33.821661940Z npm ERR! Please make sure you have the correct access rights
2022-02-22T05:57:33.821815967Z npm ERR! and the repository exists.
2022-02-22T05:57:33.822140532Z npm ERR! 
2022-02-22T05:57:33.822437945Z npm ERR! exited with error code: 128