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 ('a6a21dd52c4565e8c5e8bd7595d45faa', -1, 1438222338, 1438222338, '6b15b7a3', 29, 0, 0)

Line : 187
File : sessions.php