Can't deserialize my POJO sent from an Angular http post request on my Springboot POST mapped function

For context, my app is a coffee shop and I want to sent a an array of items over to my springboot backend. However jackson gives the exception:

Cannot construct instance of `me.andrewq.coffeeshop.menu_items.Menu` 
(no Creators, like default constructor, exist): cannot deserialize from Object value 
(no delegate- or property-based Creator)
at [Source: (PushbackInputStream); line: 1, column: 3] (through reference chain: 
java.util.ArrayList[0])] with root cause
com.fasterxml.jackson.databind.exc.InvalidDefinitionException: 
Cannot construct instance of `me.andrewq.coffeeshop.menu_items.Menu` 
(no Creators, like default constructor, exist): cannot deserialize from Object value 
(no delegate- or property-based Creator)
at [Source: (PushbackInputStream); line: 1, column: 3] (through reference chain: 
java.util.ArrayList[0]).

This is what the item's class looks like (after omitting the setters and getters):

public class Menu {
private int productId;
private String name;
private double price;
private String[][] productOptions;
private String type;
// These 3 variables belong to drinks. The creams and sugars more so for coffees
private String currentSize;
private Integer creams;
private Integer sugars;
public Menu(int productId, String name, double price, String productOptions, String type){
this.productId = productId;
this.name = name;
this.price = price;
this.productOptions = convertOptions(productOptions);
this.type = type;
}
/**
* Used for converting the product options which is a key-value pair seperated by a ',' in the DB, into a 2D array in this class.
* @param options
* @return
*/
private String[][] convertOptions(String options) {
String[] optionPairs = options.split(",");
//hard coded b/c I know that these are pairs 
String retVal[][] = new String[optionPairs.length][2];
for(int i = 0; i < optionPairs.length; ++i){
String[] temp = optionPairs[i].split(":");
retVal[i] =  temp;
}
return retVal;
}
@Override
public String toString(){
return String.format("{productId: %i, name: %s}", this.productId, this.name);
}
}

The request is received in a controller class as:

@RestController
public class OrderController {
@CrossOrigin(origins = "http://localhost:4200")
@PostMapping(path = "/guestOrder")
public String order(@RequestBody List<Menu> order){
for(Menu item: order){
System.out.println(item.toString());
}
return "Sending order worked";
}
}

In Angular the item is defined as:

export interface Menu {
productId: number;
name: string;
price: number;
productOptions: string[][];
type: string;
// additional field for drinks and coffees
currentSize: string;
creams: number;
sugars: number;
}

And the http request call is: this.http.post<string>(`${this.url}/guestOrder`, this.orderItems); where http: HttpClient and orderItems: Menu[].

Without formatting the JSON, error occurs at column 65 of the JSON string:

[{"productId":1,"name":"Iced Coffee","price":2,"productOptions":[["S","2.00"],["M","2.50"],["L","3.00"]],"type":"IC","currentSize":"S","creams":0,"sugars":0}]

This is at the first bracket of productOptions

The exception actually says it pretty well - you need to add a default constructor to your POJO class.

The JSON parser works by first creating an empty instance and then calling the setter method for each property in encounters in the JSON text. A property that is not contained in the JSON remains untouched and therefore has the value that the default constructor assigns to it (usually null unless you set it to something else).

I hope the are getters and setters that you say are omitted for clarity, are indeed there, otherwise it won't work as well.