Not null reference a null or transient value - spring-boot

Question

So i am trying to achieve oneToone relationship between two entity classes.First class is a customer entity class which have two foreign keys buyer_id and seller_id.So what i want initially is that when the user fills the initial credentials in the website the buyer_id and seller_id field should be null and after the user fills the required information for the buyer or seller i will update the row of the corresponding customer and add the buyer_id and seller_id.But when i try to create a customer entry i am getting this error that buyer_id cannot be null?
This is my customer table
#Entity
#Table(name = "Customer")
public class Customer {
public enum Status{
ACTIVE,
IN_ACTIVE
}
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id")
private long id;
#OneToOne(fetch = FetchType.LAZY,optional = true,cascade=CascadeType.ALL)
#JoinColumn(name = "seller_id",nullable = true,referencedColumnName = "id",updatable = true)
#Basic(optional = true)
private Seller seller_id;
#OneToOne(fetch=FetchType.LAZY,optional = true,cascade=CascadeType.ALL)
#JoinColumn(name = "buyer_id", nullable = true,referencedColumnName="id",updatable = true)
#Basic(optional = true)
private Buyer buyer_id;
#OneToOne(fetch=FetchType.LAZY,optional = false,cascade = CascadeType.ALL)
#JoinColumn(name = "user_id",nullable = false,unique = true,referencedColumnName = "id")
private User user_id;
public Buyer getBuyer_id() {
return buyer_id;
}
public void setBuyer_id(Buyer buyer_id) {
this.buyer_id = buyer_id;
}
#Column(name = "Name")
String name;
#Enumerated(EnumType.STRING)
#Column(name = "Status")
private Status status;
public Customer(String name,Status status){
this.name=name;
this.status = status;
}
public Customer(){
}
public Seller getSeller_id() {
return seller_id;
}
public void setSeller_id(Seller seller_id) {
this.seller_id = seller_id;
}
public User getUser_id() {
return user_id;
}
public void setUser_id(User user_id) {
this.user_id = user_id;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public User getUser() {
return user_id;
}
public void setUser(User user) {
this.user_id = user;
}
public Status getStatus() {
return status;
}
public void setStatus(Status status) {
this.status = status;
}
}
This is my buyer table
#Entity
#Table(name="Buyer")
public class Buyer {
#Id
#Column(name = "id") private long id;
#Column(name = "GSTIN")
String GSTIN;
#Column(name = "Legal_Document")
#Lob
private byte[] legalDocument;
#OneToOne(fetch=FetchType.LAZY,
cascade = CascadeType.ALL,
mappedBy = "buyer_id")
#JsonIgnore
private Customer customer;
#Column(name = "Authorized_person_name")
String authorized_person_name;
#Column(name = "Authorized_person_email")
String authorized_person_email;
}
This is my seller table
#Entity
#Table(name = "Seller")
public class Seller {
#Id
#Nullable
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id")
private long id;
#Column(name = "GSTIN")
private String GSTIN;
#Column(name = "GST_Document")
#Lob
private byte[] gst_document;
#OneToOne(fetch=FetchType.LAZY,
cascade = CascadeType.ALL,
mappedBy = "seller_id")
#JsonIgnore
private Customer customer;
// #OneToOne(fetch = FetchType.LAZY,
// cascade = CascadeType.ALL,
// mappedBy = "sellerId")
// #JsonIgnore
// private PickupAddress pickupAddress;
#Column(name = "name")
private String name;
#Column(name = "email")
private String email;
public String getGSTIN() {
return GSTIN;
}
public void setGSTIN(String GSTIN) {
this.GSTIN = GSTIN;
}
public byte[] getGst_document() {
return gst_document;
}
public void setGst_document(byte[] gst_document) {
this.gst_document = gst_document;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
}