I am getting an empty file content from webhook response about the transaction details, It was working fine before, Now it is not working, I just changed the mode from active to inactive and test the webhook end point, it shows the ping is successfull but the transaction details is empty.Can anybody please help me to know what is going on?
When your endpoint is inactive I think you have to send a post request to auth.net webhooks endpoint to test and that the test button won't deliver a payload.
There is a section on the documentation "testing a webhook" that explains how this test works. You have to base64 encode your login credentials before making the request. It is all explained in the docs.
If you're consistently getting a payload from actual sandbox/production transactions then IMO you don't need to do any further testing to validate that your endpoint works. Doesn't really matter what it does in inactive mode.