phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 2

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in) VALUES ('51bfe1c0eb5560ca4d68d08ec1f7b025', -1, 1527476261, 1527476261, '1714f0c1', 1, 0)

Line : 158
File : sessions.php