We had this issue in past when we started getting below error in most of the entities of Click Dimensions.
The issue can occur if the password would have expired or changed for the Service Credentials account of Click Dimensions.
Go to Settings à ClickDimensions Settings à Service Credentials.
In our case it wasn’t changed but we were still getting the issue. The only way we were able to fix it was to specify a different account for the Service Credentials.
Hope it helps.