To file a report in Google Maps, you have to be using the mobile app for Android or iOS, and you have to be in navigation mode. Tap the report icon on the right (the plus symbol inside a speech bubble), or swipe up on the estimated journey time and tap Add a report.

On the map, select the road you want to fix. On the left, verify the road segment selected. Under "Edit information," select the type of info you want to fix and enter the correction. Submit.

In plain text at the bottom right of the map, click Send feedback. Tip: For some routes, you may need to expand the directions on the left before you select which directions are wrong. Select the type of problem, then click Submit.