Error message after successfully pushing to Heroku

Having spoken to Heroku support recently regarding this, you can pass the below environment variables when pushing to your Heroku remote to reveal more about what's going on:

GIT_CURL_VERBOSE=1 GIT_TRACE=1 git push https://heroku:[email protected]/app-name.git develop:develop

Just had this issue myself. What worked for me was this response directly from Heroku Support

$ Upgrade GIT on your local machine
$ heroku plugins:install heroku-repo
$ heroku repo:reset -a <app-name>
$ git commit --allow-empty -m "Reset repo"
$ git push heroku master