Oauth APP, can't get the token and get an error "Error: Client network socket disconnected before secure TLS connection was established"

Hi,
I got this issue for several days: i am now creating a Oauth app with github.
After getting the code, i did something below:

async ctx => {
const requestToken = ctx.request.query.code;// get the code from redirect_uri
console.log(‘authorization code:’, requestToken);

const tokenResponse = await axios({
method: ‘post’,
url: 'https://github.com/login/oauth/access_token?’ +
client_id=${clientID}& +
client_secret=${clientSecret}& +
code=${requestToken},
headers: {
accept: ‘application/json’
}
});
const accessToken = tokenResponse.data.access_token;
console.log(access token: ${accessToken});

but i get error:
Error: Client network socket disconnected before secure TLS connection was established
at TLSSocket.onConnectEnd (_tls_wrap.js:1092:19)
at Object.onceWrapper (events.js:286:20)
at TLSSocket.emit (events.js:203:15)
at endReadableNT (_stream_readable.js:1129:12)
at process._tickCallback (internal/process/next_tick.js:63:19)

Anyone can help me on this ? thanks so much.