AC1200 cable modem router

More info is needed. 

1. AC1200 is a speed, not a model. What model is it? 

2. Is the wifi dropping or is the internet not working? What I mean by this are devices showing as connected but no internet connection or are they dropping off the wifi entirely? A better explaination of what's going on helps.

3. If its a cable modem/router combo device please include a screen snip of your connections page and your logs?

4. Firmware on it?

5. Isp you're using? 

6. Is it all devices (both wired and wireless), just wireless, or just a single device?

Anymore you can expand can help us to help you. We struggle to help with minimal info.