Can't delete all from Sequelize n:m associated table - node.js

Question

I am trying to delete all contents from a n:m association table.
I have the tables: MenuItems and UserGroups like this, but I am using migrations to genererate the database:
MenuItems
module.exports = (sequelize, DataTypes) => {
const MenuItems = sequelize.define('MenuItems', {
title: {
type: DataTypes.STRING,
allowNull: false
}
// more fields...
}, {
freezeTableName: true
});
MenuItems.associate = function(models) {
MenuItems.belongsToMany(models.UserGroups, { through: 'MenuItemUserGroups' });
};
UserGroups
module.exports = (sequelize, DataTypes) => {
const UserGroups = sequelize.define('UserGroups', {
name: {
type: DataTypes.STRING,
unique: true
}
}, {
freezeTableName: true
});
UserGroups.associate = function(models) {
// Associations to other models
UserGroups.belongsToMany(models.MenuItems, { through: 'MenuItemUserGroups' });
};
return UserGroups;
};
The association table is generated with the following migration:
up: (queryInterface, Sequelize) => {
return queryInterface.createTable('MenuItemUserGroups', {
id: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: Sequelize.INTEGER
},
menuItemId: {
type: Sequelize.INTEGER,
allowNull: false,
references: {
model: 'MenuItems',
key: 'id'
},
onUpdate: 'cascade',
onDelete: 'cascade'
},
userGroupId: {
type: Sequelize.INTEGER,
allowNull: false,
references: {
model: 'UserGroups',
key: 'id'
},
onUpdate: 'cascade',
onDelete: 'cascade'
}
//more fields
});
}
I try to delete using the following sequelize code:
models.MenuItems.findOne({ where: { id: 1 }, include: [{ all: true }] }).then(menuItem => {
if(req.body.userGroups.length <= 0) {
menuItem.setUserGroups([]).then(result => {
console.log(result);
});
The SQL that is generated is the following:
DELETE FROM `MenuItemUserGroups` WHERE `UserGroupId` = 1 AND `MenuItemId` IN (NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL)
[ 0 ]
where UserGroupId IN (NULL) will always return nothing. If that part is removed, the query works.
Could this have something to do with some naming convention?