Unidentified Network and Public Network

I have a TP link Router TD-W8961ND and it keeps switching from Home Network to Unidentified Network and Public Network. And of course no internet connection.

I have no idea why this is doing this and I cannot switch it back to Home Network. The only way I can get Home Network back is to do a Factory Reset and then put my details back in and off we go again until it switches.

Any help or ideas why this is doing this.