I deleted my site and recreated it again. The same thing happens again. Although I got a little more detailed message for one of my early failed git push commands:
Uploading LFS objects: 37% (1094/2968), 220 MB | 767 KB/s, done.
Repository or object not found: https://[SITE_ID].netlify.com/.netlify/large-media/verify
Check that it exists and that you have proper access to it
Repository or object not found: https://[SITE_ID].netlify.com/.netlify/large-media/verify
Check that it exists and that you have proper access to it
Post https://[SITE_ID].netlify.com/.netlify/large-media/verify: stream error: stream ID 17; NO_ERROR
Repository or object not found: https://[SITE_ID].netlify.com/.netlify/large-media/verify
Check that it exists and that you have proper access to it
Post https://[SITE_ID].netlify.com/.netlify/large-media/verify: http2: server sent GOAWAY and closed the connection; LastStreamID=17, ErrCode=ENHANCE_YOUR_CALM, debug=""
Repository or object not found: https://[SITE_ID].netlify.com/.netlify/large-media/verify
Check that it exists and that you have proper access to it
batch response: Expected json type, got: "text/plain; charset=utf-8"
batch response: Expected json type, got: "text/plain; charset=utf-8"
...
batch response: Expected json type, got: "text/plain; charset=utf-8"
error: failed to push some refs to 'git@github.com:[ORG]/[REPO].git'