phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '773264fc97c562eeaee4374c79f33967' for key 'PRIMARY'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('773264fc97c562eeaee4374c79f33967', -1, 1432480997, 1432480997, 'adf538d2', 15, 0, 0)

Line : 245
File : sessions.php