Cannot set properties of undefined (setting ‘xxx‘)

This error message occurs when you try to set a property on an undefined variable. This means that the variable you are trying to access or modify has not been defined or initialized yet.

To fix this error, you need to make sure that the variable is defined and initialized before trying to access or modify its properties. You can do this by declaring the variable before using it or by assigning a value to it.

For example:

let myVariable; // declare the variable
myVariable = {}; // initialize the variable with an empty object
myVariable.xxx = 'some value'; // set the property 'xxx'

Alternatively, you can use a default value for the variable when declaring it, like this:

let myVariable = {}; // initialize the variable with an empty object
myVariable.xxx = 'some value'; // set the property 'xxx'

Make sure to check your code for any typos or syntax errors that might cause the variable to be undefined. Also, check whether the variable is being passed correctly between different functions or modules.