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 ('8b7e0a9f4e18ec3962abd2cc8b56a13e', -1, 1406284118, 1406284118, '17171c17', -1, 0)

Line : 158
File : sessions.php