I have implemented Android app links based on the below links.
https://developer.android.com/studio/write/app-link-indexing.html
https://developer.android.com/trai
I got into the same issue as it was working perfectly on the signed apk which was not uploaded to the playstore.
Later I found out that I need to add the SHA256 key from PlayConsole By going to Application Dashboard in Play Console then Release Management --> App Signing and there you will find SHA-256 certificate fingerprint Use this SHA-256 in assetlinks.json at https://ourdomain/.well-known/assetlinks.json and then reinstall the app from playstore It started working fine for me