Have they sent someone out? Have you ruled out the router?

I'd try to connect directly to the modem with a device if possible and see if that device has a consistent connection or not (means you won't have wifi for a day or two unfortunately). If so, probably the router, if not then the ISP probably will need to send someone out because it's the modem, or the drop cable, or something further back down the line that they also own.

These issues were always the worst to troubleshoot because there's very little they can do for you over the phone, and not everyone is competent/thorough so sometimes if you've had one tech out there might be something they should have caught but didn't.

If you can record the specific times it goes down for a while that might also help anyone who's trying to fix it because they may be able to check the recent history for the modem's internet connectivity and if that's down when your internet is down it's narrowed down to not the router at least.

Sorry if any of this fails to help (probably will, honestly most intermittent issues callers were repeat callers IME). Honestly I had to have like three techs out a few years ago for mine, it's a hassle.

I had this for years until the ISP finally fucking installed fiber on my street and I switched to that from DSL

what is it? cable or fiber?

i think you should login to the router and check the stats. the modem has to connect and handshake with the isp maybe its dropping out because the signal is weak?

also just to check its not dns, use dns over https on your browser.

Have you checked all your connections?

You'd think that because everything is digital, a loose connection is either on or off, but in reality it can have all sorts of cursed symptom patterns.

uh, sorry, you weren’t supposed to notice

Is it happening at consistent times? Also next time it goes out, see if you can plug an ethernet cable into the router and see if you're getting a connection over ethernet. Also is the connection like completely severed or just a very high rate of dropped packets / slowness?

It could really be anything. I had an issue sort of like this and the root cause was the router had a “helpful” option, called Dynamic Frequency Switching. In my layman understanding, this merged the 2.4 and 5.0 GHz channels into one SSID, and left the channel selection up to the router. So I was having issues with losing connection during vidya games when my router decided it was time to switch networks.

When does it go out? What time does it go out? How long are you using the Internet before it goes out?

Is it an ISP provided router? They're usually terrible I always use my own.

However it depends on the type on internet as well. Fiber tends to be quite stable but when I was on copper lines my internet was up and down all the time with speeds dropping to unusable levels. Then I'd open a support ticket, some engineer would fix it, a few weeks later back to the same problem.

My moneys in the router it usually is most of the time. Although you'll have to check your ISP supports it.

Does it happen when wired and wireless or just wireless?

Probably a setting on your router that is bugged?