1615 Error: Prepared statement needs to be re-prepared in MySQL

Question

I have following stored procedure which was executing perfectly. But since morning I am getting the error

Prepared statement needs to be re-prepared

I tried all the things but could not get any help.

CREATE PROCEDURE `SP_FEEDBACK_REPORT`(
    IN p_eventID INT(10),
    IN p_sessionID INT(10)
)
BEGIN
    SET SESSION group_concat_max_len = 10240;
    SET @sqlQry = NULL;

    SELECT GROUP_CONCAT(DISTINCT CONCAT(' MAX( IF(attended_id = ', attended_id, ', IF(answer_id !=47, (SELECT key_value FROM tblrating_master WHERE key_id=answer_id), comments),NULL)) AS ', attendee_name)) INTO @sqlQry FROM vwfeedback_report WHERE event_id=p_eventID AND session_id=p_sessionID;

    SET @sqlQry = CONCAT('SELECT question, ', @sqlQry, ' FROM vwfeedback_report WHERE event_id=', p_eventID,' AND session_id=', p_sessionID,' GROUP BY feedback_id;');
    -- SELECT @sqlQry FROM DUAL;
    PREPARE stmt FROM @sqlQry;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;
    SET SESSION group_concat_max_len = 1024;
END;

Please help