unwary

Not alert to danger, problems, or deception.

Not wary; not vigilant against danger; not cautious; unguarded; precipitate; heedless; careless.

Unexpected.

Not vigilant against danger; not wary or cautious; unguarded; precipitate; heedless; careless.

Unexpected; unforeseen; unware.

Lacking caution as a result of naïveté or inexperience

Unprepared; not watchful

not alert to danger or deception