I have a problem with this settings of nghttpx:
nghttpx -f0.0.0.0,443 -bnginx.domain.com,443;;proto=h2;tls ./nghttpx.key ./nghttpx.crt

When I try to connect to nghttpx with curl https://app.mydomain2.com -k i get:

HTTP/1.1 503 Service Unavailable
There are no any traces in nginx logs

The same problem doesn't exist with:
nghttpx -f'*,80;no-tls' -b'nginx.domain.com,443;;proto=h2;tls' -k

Any clues where should I search for answer?