Typeerror: Cannot perform 'get' on a proxy that has been revoked

Question

Hello

I am having trouble working with asynchronous Node mode with Bot Framework 4. When trying to execute the code below, it generates the error: Typeerror: Cannot perform 'get' on a proxy that has been revoked

The problem I saw is calling step.context.sendActivity(result[0].tag) inside con.query(). They could help me out?

var sql = "";
sql += " select tag ";
sql += " from tagconfig ";
sql += " where descricao like '%" + step.values.sensor + "%'; ";
    
con.query(sql, function (err, result) {        
   sql = " ";
   sql += " select `" + result[0].tag + "` as tag, dathor ";
   sql += " from tagdados ";
   sql += " order by dathor desc ";
   sql += " limit 1 ";
    
   con.query(sql, function (err, result) {
      step.context.sendActivity(result[0].tag);
      if (err) throw err;
   });                         
    
   if (err) throw err;
});