"Failed to authenticate user"

Hello,

First of all great library to use group calling.

We are facing one issue when trying to call, below are the steps and error.

Steps:
- Login with username and password.
- Create new group with 4-5 members
- Start Group Video call.
- Trying to call. We are getting alert "Failed to join the conference call" and we are getting below error:

Error Domain=com.alamofire.error.serialization.response Code=-1011 "Request failed: internal server error (500)" UserInfo={NSLocalizedDescription=Request failed: internal server error (500), com.matrixsdk.httpclient.error.response.data={
message = "Failed to authenticate user";
}, NSErrorFailingURLKey=https://scalar-staging.riot.im/scalar/api/register?v=1.1, com.alamofire.serialization.response.error.data=<7b226d65 73736167 65223a22 4661696c 65642074 6f206175 7468656e 74696361 74652075 73657222 7d>, com.alamofire.serialization.response.error.response= { URL: https://scalar-staging.riot.im/scalar/api/register?v=1.1 } { Status Code: 500, Headers {
"Access-Control-Allow-Origin" = (
"*"
);
"Content-Length" = (
41
);
"Content-Type" = (
"application/json"
);
Date = (
"Mon, 17 Jun 2019 07:57:35 GMT"
);
Server = (
cloudflare
);
"access-control-allow-headers" = (
"Origin, X-Requested-With, Content-Type, Accept, Authorization"
);
"access-control-allow-methods" = (
"GET, POST, PUT, DELETE, OPTIONS"
);
"cf-ray" = (
"4e83793a3ccdce27-LHR"
);
"expect-ct" = (
"max-age=604800, report-uri=\"https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct\""
);
} }}

Help would be appreciated.
Many Thanks in advance.

The report identifies the group video-call flow and the Scalar /scalar/api/register?v=1.1 endpoint, but no source file or test. Start by reproducing the login, group creation, and call sequence while inspecting that registration request and its authentication response. Done means the request no longer returns the 500 error and the conference call can be joined.

Written by the indexing model from the issue text.