To begin with, my firebase console is showing an error saying…

https://mydomain.mydomain1.co.uk is not connected properly
Your Dynamic Links path prefix is not configured in firebase.json. Check your firebase.json configuration and try again.

My firebase.json does not show anything relating to DL… its contents are as follows…

{
  "firestore": {
    "rules": "firestore.rules",
    "indexes": "firestore.indexes.json"
  }
}

However, when I send a DL from my iOS app to Android to open, I get a 403 page but when I do the opposite i.e. Android app to iOS, it works fine. I am not sure where am I missing something here. Thanks