phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '55191b2a8f65771d67abe946acbcec3a' for key 'phpbb_sessions.PRIMARY'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('55191b2a8f65771d67abe946acbcec3a', -1, 1770884483, 1770884483, 'd849d88f', -4, 0, 0)

Line : 187
File : sessions.php