[File my return error: "No endpoint"?]

Update: It was (somehow) fixed and I was able to fill my return.

[File my return error: "No endpoint"?]

Good morning. When I try to "File my return now" after some seconds I get an error message with the following content.

"There was no endpoint listening at https://dtdcfengpn002.dttax.local:55715/OnlineService.svc that could accept the message. This is often caused by an incorrect address or SOAP action. See InnerException, if present, for more details."

How can I fix this and file my tax return? Thanks for any help.