phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '7f788172e0500eb914f6a241a108f969' 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 ('7f788172e0500eb914f6a241a108f969', -1, 1771967978, 1771967978, 'd849d8bf', -4, 0, 0)

Line : 187
File : sessions.php