Data Source credentials do not connect

Hi All

I'm trying to set up automatic refreshing for my data, dashboards and alerts.

Whenever I enter my data source credentials the pop-up just keeps loading and does not do anything- see below.

The data source error I get before trying to edit credentials is:

• Data source errorScheduled refresh is disabled because at least one data source is missing credentials. To start the refresh again, go to this dataset's settings page and enter credentials for all data sources. Then reactivate scheduled refresh.

Any advice would be appreciated.