I have a pretty simple amcrest that was working at one point (and is working via the direct url to the camera). The only related errors I see in the log are:
2020-02-18 22:17:30 ERROR (MainThread) [homeassistant.components.camera] Error requesting stream: Camera is off
2020-02-18 22:17:30 WARNING (MainThread) [homeassistant.components.http.ban] Login attempt or request with invalid authentication from 172.30.33.4