To reproduce:
1. Open attached project
2. Open FreeCameraDemo scene
3. Press Play
4. Click Singapore or Caribbean Button
5. Notice that it sets InputField.text through script
6. Press W/A/S/D keys
7. Notice that input field captures the keystrokes

Input field only captures the keystrokes if W/S/D/A are pressed after clicking button. It doesn't capture if other keys are pressed after clicking button.