is it possible to send push notification in batch of group ids using FCM?

Anyone can tell me how to send a push notification to a batch of group ids using FCM.

I tried

url = "https://fcm.googleapis.com/fcm/send"

headers = {
    "Content-Type":"application/json",
    "Authorization":"key={}".format(API_KEY)
    }

body = {
    "registration_ids":["group_id1","group_id2",...."group_idn"],
    "data": {
        "hello": "This is a Firebase Cloud Messaging Device Group Message!",
        }
    }

but it is giving me error. {"multicast_id":6704816187425274139,"success":0,"failure":1,"canonical_ids":0,"results":[{"error":"NotRegistered"}]}