phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'cdbca784b862d2a31d05a0fed6af4d18' 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 ('cdbca784b862d2a31d05a0fed6af4d18', -1, 1503134691, 1503134691, '36c647b8', -4, 0, 0)

Line : 174
File : sessions.php