phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '26716da1f63226e78353cb6b11bb657c' 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 ('26716da1f63226e78353cb6b11bb657c', -1, 1398405913, 1398405913, '36c43904', 17, 0, 0)

Line : 292
File : sessions.php