Try carrying out a Service Status Health Check.
Please ensure your Community Profile Personal Information (Click here) includes your name, address, current TalkTalk landline 'phone number and an alternate number (mobile recommended). Add, then scroll down and save changes. The TalkTalk Community Team OCE will then be able to link to your TalkTalk service account.
Have you got any device that you can connect to the router using the supplied Ethernet cable? Just to rule out an interference issue with the Wi-Fi connection to the router.
When the time comes that the Internet connection disappears what is the status of the router leds?
And what does the sync speed of the router report?
I'm sorry to hear this and I'll take a look now. I've run a test on the line which hasn't detected a fault and the connection looks stable. Do any of the lights change on the router when the connection stops working?
Ok thanks for the additional information. Is it always exactly at midnight? Do you have any devices set on a timer to come on/off at this time? Do you experience any issues with the voice service at the same time such as no dial tone?
Line tests aren't showing any interruptions to your service between 12am and 1am (or any other time of the day), Are all devices unable to connect at the same time? Do you get an error message when you can't connect?
Approximately how long has this been happening?
OK, thanks, and you get the error message on more than one device at the time? Does it happen when you're doing anything specifically or can it happens when gaming, browsing, streaming etc?
...the router and Service Status Heath Check are both indicating the service is up and running.
Try using the Chrome or Firefox browsers. Available for Windows, Mac, Apple and Android. And just in case you've got security software running a scheduled scan just disable that whilst testing at this time.