Sequelize associations doesn't work

i've got this two models

module.exports = function (sequelize, DataTypes)
return sequelize.define('transportationType',
description:
type: DataTypes.STRING,
allowNull : false

)



module.exports = function (sequelize, DataTypes)
return sequelize.define('Transportation',
code: DataTypes.INTEGER,
description: DataTypes.STRING,
seatQty: DataTypes.INTEGER
)



and here is the association

db.Transportation.belongsTo(db.TransportationType);


and i make an api like this

var code = parseInt(req.body.code);
var desc = req.body.desc;
var seat = parseInt(req.body.seat);
var type = parseInt(req.body.TransportationType);
db.TransportationType.findById(type)
.then(snap =>
db.Transportation.setTransportationType(snap);
db.Transportation.create(
code: code,
description: desc,
seatQty: seat
)
.then(data => console.log(data))
.catch(err => res.json(err));
)


when i run the code with postman , the console said

db.Transportation.setTransportationType is not a function.

db.Transportation.setTransportationType is not a function.

I'm sure the docs say it will run, but it's not

setTransportationType

Transportation

.setTransportationType

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.