phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1194 Table '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 ('563f40a62e368babea74868ca21e8a3f', -1, 1438665674, 1438665674, '36e21b68', -1, 0, 0)

Line : 172
File : sessions.php