There could be a variety of reasons why cTrader may have disconnected or is not responding. We recommend that you check that your internet connection is working, your credentials are accurate and that your device has the correct specifications to handle the software.
From there, have as look at cTrader’s troubleshooting guides for other steps.
Below are the links to the troubleshooting guides for each cTrader platform:
Desktop: https://help.ctrader.com/ctrader/miscellaneous/connectivity-issues-guide/
Android: https://help.ctrader.com/ctrader-mobile-android/troubleshoot/
If problems persist, please check the cTrader trading support help forums at https://ctrader.com/forum/. Here you will find the designated cTrader support team that will be able to walk you through any platform issues.