Spring JPA #ManyToOne and #OneToMany does not update all - spring-boot

Question

I have two classes Post and Comment, one post can have multiple comments. So I have created my classes as follows:
Post:
#Entity
#Table(name = "posts")
public class Post extends AuditModel {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#NotNull
#Size(max = 100)
#Column(unique = true)
private String title;
#NotNull
#Size(max = 250)
private String description;
#NotNull
#Lob
private String content;
#OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "post")
private Set<Comment> comments = new HashSet<>();
}
Comment:
#Entity
#Table(name = "comments")
public class Comment extends AuditModel {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#NotNull
#Lob
private String text;
#ManyToOne(fetch = FetchType.EAGER, optional = false)
#JoinColumn(name = "post_id", nullable = false)
#OnDelete(action = OnDeleteAction.CASCADE)
#JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
#JsonIdentityReference(alwaysAsId = true)
#JsonProperty("post_id")
private Post post;
}
Post method:
#PostMapping("/posts")
public Post createPost(#Valid #RequestBody Post post) {
return postRepository.save(post);
}
Swagger request:
{
"id": 0,
"title": "string",
"description": "string",
"content": "string",
"comments": [
{
"id": 0,
"text": "string",
"post_id": 0
}
]
}
When I do a POST using the above schema, I am expecting that hibernate will insert data in both the tables. But instead, I get below error:
Resolved [org.springframework.http.converter.HttpMessageNotReadableException: JSON parse error: Unresolved forward references for: ; nested exception is com.fasterxml.jackson.databind.deser.UnresolvedForwardReference: Unresolved forward references for:
at [Source: (PushbackInputStream); line: 1, column: 117]Object id [1] (for `com.example.jpa.model.Post`) at [Source: (PushbackInputStream); line: 1, column: 115].]
Can someone please help me to understand this and how can I achieve my requirement?