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 ('c6bcc147546661b9307aaf9226d5215d', -1, 1438392475, 1438392475, '36e293be', -1, 0, 0)

Line : 187
File : sessions.php