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 ('9ac0f86163ec7e42f2133b748ebb409f', -1, 1438258157, 1438258157, '36e2f6a0', -1, 0, 0)

Line : 187
File : sessions.php