To dream of a billboard represents a person or situation that is giving you an obvious “sign” or signal. It may also symbolize a person or situation that is trying very hard to draw your attention to a positive or desirable quality about themselves.
A billboard common reflects people who are flirting with others or trying to draw attention to how attractive they are.
To dream of being unable to read may reflect your feelings of being left out of the loop. You didn’t “get” a signal, fact or bit of information that other people picked up easily. It may also be a sign that you are too distracted or have tunnel vision in current project. Missing a billboard may also reflect problems picking up social cues or reading body language.
To dream of missing may be a sign that that you need to take note of in your path toward your goals. Consider what advice the billboard is trying to convey to you.
Example: A woman dreamed of driving past offering her a product. In real life she was talking to a man on the phone who was describing himself as being very attractive while hitting on her.