Angular: find and replace array from nested array

I am struggling to find and replace array in following case.

I need to replace comments array of particular post_id (e.g. 89) from data array with comments array of postDetails and result should be data array with replaced comments of that post_id.

     "data": [
                {
                    "post_id": "89",
                    "event_id": null,
                    "title": null,
                    "description": null,
                    "links": null,
                    "user_id": "28",
                    "user_name": "Namrata Tambare",
                    "user_profile_path": "profile-images/20220118060204-cartoon-dp-for-girls-whatsapp.jpg",
                    "mediaData": [
                        {
                            "id": 119,
                            "social_media_posts_id": 82,
                            "media_type": "image",
                            "images": "20220111070528-123.jpg",
                            "videos": null,
                            "file_path": "images/20220111070528-123.jpg"
                        },
                        {
                            "id": 120,
                            "social_media_posts_id": 82,
                            "media_type": "image",
                            "images": "20220111070528-320.png",
                            "videos": null,
                            "file_path": "images/20220111070528-320.png"
                        },
                        {
                            "id": 121,
                            "social_media_posts_id": 82,
                            "media_type": "video",
                            "images": null,
                            "videos": "20220111070528-pexels-c-technical-6153734.mp4",
                            "file_path": "videos/20220111070528-pexels-c-technical-6153734.mp4"
                        }
                    ],
                    "likeCount": 1,
                    "alreadyLike": "yes",
                    "comments": [
                        {
                            "id": 90,
                            "post_id": 82,
                            "comment": "efretret",
                            "comment_by_user": 28,
                            "parent_id": 0,
                            "created_at": "2022-01-17T06:28:49.000000Z",
                            "post_comment_users": {
                                "id": 28,
                                "first_name": "Na",
                                "last_name": "Ta",
                                "profile": "20220118060204-cartoon-dp-for-girls-whatsapp.jpg",
                                "profile_path": "profile-images/20220118060204-cartoon-dp-for-girls-whatsapp.jpg"
                            },
                            "post_comment_replys": []
                        }
                    ],
                    "event_total_going": "",
                    "event_total_not_going": "",
                    "event_total_maybe": "",
                    "event_start_date": null,
                    "event_location": null,
                    "event_status": null,
                    "post_created_at": "2022-01-11T07:05:28.000000Z"
                },
    {
    ...
    
    },
{
    ...
    
    },
{
    ...
    
    }
    ]


"postDetails": [
        {
            "id": 89,
            "user_id": 30,
            "user_name": "new nmt testing test 123",
            "user_profile": "20211025055017-ima5.png",
            "user_profile_path": "profile-images/20211025055017-ima5.png",
            "horse_id": null,
            "horse_name": "",
            "horse_profile": "",
            "horse_profile_path": "",
            "description": "test post",
            "links": null,
            "created_at": "2021-10-25T05:51:21.000000Z",
            "imagesVideos": [
                {
                    "id": 72,
                    "social_media_posts_id": 46,
                    "media_type": "image",
                    "images": "20211025055121-2514219.jpg",
                    "videos": null,
                    "file_path": "images/20211025055121-2514219.jpg",
                    "created_at": "2021-10-25T05:51:21.000000Z"
                },
                {
                    "id": 73,
                    "social_media_posts_id": 46,
                    "media_type": "video",
                    "images": null,
                    "videos": "20211025055121-pexels-video-kickstarter-5299577.mp4",
                    "file_path": "videos/20211025055121-pexels-video-kickstarter-5299577.mp4",
                    "created_at": "2021-10-25T05:51:21.000000Z"
                }
            ],
            "totalLikes": 1,
            "comments": [
                {
                    "id": 27,
                    "post_id": 46,
                    "comment": "test comment",
                    "comment_by_user": 30,
                    "parent_id": 0,
                    "created_at": "2021-10-25T05:52:16.000000Z",
                    "post_comment_users": {
                        "id": 30,
                        "first_name": "new nmt testing",
                        "last_name": "test 123",
                        "profile": "20211025055017-ima5.png",
                        "profile_path": "profile-images/20211025055017-ima5.png"
                    },
                    "post_comment_replys": []
                }
            ]
        }
    ],

by using find I can get object from data array but how can I replace comment array of that with postDetails and get whole updated data array ?

Please guide and help.