phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('3d5f706007fd26f9012d77c61a0d0b70', -1, 1747104164, 1747104164, '0a020003', 1, 0, 0)

Line : 187
File : sessions.php