Firebase Database is not showing data

it might seem ridiculous but I have tried to log out and log in but it didn't help so i changed the web browser and it worked

I had the same problem. It was the Ads blocker. Just I disabled it and data showed up.

Be careful of these sneaky extensions.

Hope it helps others.

just goto the RULES option given beside the data in Firebase and change the read,write from false to true and then click simulator and publish it.