Problem solved. Someone mention checking the nuts that tighten the license plate in the back. They were tight but left space for the lower part of the plate to move freely. I replaced the nuts for others bought at an auto part store. It was actually the license plate's lower part flying freely with speed and making the noise. Nuts replaced, license plate cannot move anymore. The noise is gone.
Problem solved. Someone mention checking the nuts that tighten the license plate in the back. They were tight but left space for the lower part of the plate to move freely. I replaced the nuts for others bought at an auto part store. It was actually the license plate's lower part flying freely with speed and making the noise. Nuts replaced, license plate cannot move anymore. The noise is gone.
I have a similar issue on my 2020 titanium, but the noise since to start at or above 40 mph, coming from the rear of the vehicle. No issues at lower speeds and other than the annoyance of the noise, there are no other issues.