My Wi-Fi cuts out every day around 2am-8am

Every day, my Wi-Fi completely cuts out around the same time. It usually starts at about 2 AM and doesn’t come back on until 8 AM. This has been going on for several weeks. I’ve had a technician come out yesterday and got a new modem. He said the wires outside were brand new and everything looks good. But I’m still experiencing the same problem right now with no Wi-Fi. I can’t look at my cameras and this is actually kind of scary because I do live alone. This has been going on for weeks. I’m not sure what to do. A couple of days ago my Wi-Fi cut off at 9:30 randomly and didn’t come back on until 8 o’clock in the morning the next day. The modem will blink from yellow to green. Then it will just constantly flash green. Or it will constantly flash yellow.