Input Form - text disappears when I press tab to move to next input

Hi, I am a newbie and designing an app using the “project management” template. I have modified the “Add Project” input popup to have two text input types (a title, and details). The problem starts when I test the form in preview. Whatever I type into the “Title” field, disappears as soon as I click on any other field on the form or press tab to go to the next input field on the popup. I have modified the popup to have one title field, two dropdown menus, and one multiline text input field.