Using hosted page returns error 503, service unavailable in the callback

I am having a problem where the hosted page we use allows user registration (ie go to the sign up tab and users are created properly on auth0) but when we try to use the user to sign in, we get data returned to our callback url, but it always returns 503 - Service Unavailable. When I check the history for the user, it shows the login failed with the 503 error. Not sure where to look to troubleshoot this further.

There is not enough information to determine what the issue could be. Please provide any additional information available in the failed login entry in the Logs section of the dashboard.

This is the error from the dashboard:

Service Unavailable

The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.

Here is a sample log entry for this failure. It actually shows that the user successfully logged in if you check under administration for this domain but the redirect is producing this error. (I’ve DELETED any identifying info for this comment).

Summary
Occurred a day ago at 2017-06-22 01:22:47.055 UTC
Type Failed Login
Description 503 Service Unavailable

Service Unavailable

The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.


Connection Username-Password-Authentication
Application Test Mobile

{
“body”: {
“wa”: “wsignin1.0”,
“wresult”: “ey-EDITED FOR THIS COMMENT-zgntzVHOnicIbVc1N6Q3c”,
“wctx”: “{"strategy":"auth0","auth0Client":"DELETED FOR THIS COMMENT","tenant":"symladmin","connection":"Username-Password-Authentication","client_id":"DELETED FOR THIS COMMENT","response_type":"code","scope":"openid","redirect_uri":"ca.visdom.visdom://symladmin.auth0.com/ios/ca.visdom.visdom/callback","realm":"Username-Password-Authentication","_timer_state":{"total":{"start":1498094565067},"metrics":{"connection":{"start":1498094565067}}},"session_user":"DELETED FOR THIS COMMENT"}”
},
“qs”: {
“legacy”: true,
“auth0Client”: “DELETED FOR THIS COMMENT”,
“connection”: “Username-Password-Authentication”,
“client_id”: “DELETED FOR THIS COMMENT”,
“response_type”: “code”,
“scope”: “openid”,
“redirect_uri”: “ca.visdom.visdom://symladmin.auth0.com/ios/ca.visdom.visdom/callback”,
“realm”: “Username-Password-Authentication”,
“_timer_state”: {
“total”: {
“start”: 1498094565067
},
“metrics”: {
“connection”: {
“start”: 1498094565067
}
}
},
“session_user”: “DELETED FOR THIS COMMENT”
},
“connection”: “Username-Password-Authentication”,
“error”: {
“message”: “\n\n503 Service Unavailable\n\n

Service Unavailable

\n

The server is temporarily unable to service your\nrequest due to maintenance downtime or capacity\nproblems. Please try again later.

\n\n”,
“oauthError”: “access_denied”,
“type”: “oauth-authorization”
},
“stats”: {
“loginsCount”: 11
}
}