The Secure Store Service application Secure Store Service Application is not accessible. The full exception text is:

Secure Store Service is not accessible

The Secure Store Service application Secure Store Service Application is not accessible. The full exception text is: The HTTP service located at https://........./SecureStoreService.svc/https is unavailable.  This could be because the service is too busy or because no endpoint was found listening at the specified address. Please ensure that the address is correct and try accessing the service again later.

Cannot complete this action as the secure store shared service is not responding Please contact Administrator.

Resolution:

1. Check AppPool Account which secure store service is running is not stopped.

Go to Inetmgr -> Find the application pool for Secure store Service  

http://soreddymanjunath.blogspot.in/2016/05/the-secure-store-service-application.html

http://soreddymanjunath.blogspot.in/2016/05/the-secure-store-service-application.html

If Stopped - start the AppPool

2.  Check if Secure store service is not started,  if not go and Start as below.

Central Admin - > Application Management -> Manage Services on the Server 

Secure Store Service -> Start

Hope this will fix the issue ,