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 ('509114a21d4ef673fa75ee907bf82729', -1, 1436006355, 1436006355, '365c8358', -1, 0)

Line : 158
File : sessions.php