Error 6001 will appear if there is a disruption to the Internet service or if the Internet connection has been lost.
Verify the connection between the TV and the router/modem. Refer to No Bravia Internet Video services available or no Internet connection for advanced troubleshooting.
Please make sure that an Internet connection speed of 2.5Mb is being transmitted. Details can be found in: How to test the speed of your Internet connection.
No solution found for your problem? As there is an issue with your Internet connection, it does not make sense to contact Sony. Instead, directly contact your Internet service provider.