phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 144 Table './forum_members/phpbb_sessions' is marked as crashed and last (automatic?) repair failed

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in) VALUES ('9b8b7c42a1074bd913ac8230309d8647', -1, 1411243122, 1411243122, '36a6088a', 21, 0)

Line : 158
File : sessions.php