Hello -  I am receiving this error when trying to connect to a second Salesforce org. 
 
System.CalloutException: We couldn't access the credential(s). You might not have the required permissions, or the external credential "SitCopyExternal" might not exist.

I have full CRUD on external credentials. Below is the named credential,  external credentials, and authentication provider. Any idea what's configured incorrectly? 



 

hi
i am new to salesforce platform.
Install a simple Apex class, write unit tests that achieve 100% code coverage for the class, and run your Apex tests.The Apex class to test is called 'VerifyDate', and the code is available here. Copy and paste this class into your Developer Edition via the Developer Console.
'VerifyDate' is a class which tests if a date is within a proper range, and if not will return a date that occurs at the end of the month within the range.
The unit tests must be in a separate test class called 'TestVerifyDate'.
The unit tests must cover scenarios for all lines of code included in the Apex class, resulting in 100% code coverage.
Run your test class at least once (via the Developer Console) before attempting to verify this challenge.

In the above challege i am not able to write a 'TestVerifyDate' class. I dont unsertstand how to write it for a date.
plz help..