phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO docttorrdiscluc_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('b4ec2f196099ef6117f1c4821a0b2c1a', -1, 1545128891, 1545128891, '12d45dea', -4, 0, 0)

Line : 190
File : sessions.php