Hello,

I have an error when I try to add a label on an issue, following this documentation.

Here is how I do it:

$labels = $client->api('issue')->labels()->add('matthieu-rolland', 'test-issuebot', 51, 'Fixed');

And here is what I get:

PHP Fatal error: Uncaught Github\Exception\RuntimeException: Invalid request. No subschema in "anyOf" matched.

When I debug I see that the response I get is actually:

ERROR 422 Unprocessable Entity

I didn't manage to identify the cause of this problem...

Some more information:

• It does work when I call github's API directly via postman with the same github token
• While debugging I saw that the URI and HTTP methods seem correct (but maybe not until the end?)
• I'm not sure about the request's body
• VERSION 2.12.1