phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 145 Table './phpBB/phpbb_sessions' is marked as crashed and should be repaired

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('478ec28b876bff0da04f1a43c5236164', -1, 1427725309, 1427725309, '36a3beaa', -4, 0, 0)

Line : 187
File : sessions.php