Hi Sandy,
On Save action, you were redirecting user to Details page as you might be using Destination widget at the end of your action to redirect the user on details page.
But now, you have might have replaced the Destination Widget with End widget, which will not let your user to navigate to details page, instead stay on the same page.

So, this not any problem, bug or issue. It is how Outsystems is designed and works.
Also after submission of form data with the current scenario if you want to refresh the form for the new input then you must change the submit action of the Save button to Ajax Submit. Reassign the Form variables with default values and Ajax Refresh the Form too clear its contents.
Regards,
Nikhil