When executing the code ticker.Connect(); the error appears at Ticker_OnError event. Then again the following message appears: "Error while connecting. Message: The remote server returned an error: (403) Forbidden."
My API key and token are correct, I can get the list of instruments and exchanges. I tried disabling the firewall, but I got the same error.
The instruments master dump doesn't have authentication. You need to re-login and create a new access token. It looks like session is expired based on the above message.