There are a few possible reasons why your Invisi-Tag RFID Reader is not connecting to the app. Here are some troubleshooting tips:

*1. Make sure the reader is turned on and charged.* The reader should have a green light on when it is turned on. If the light is red, the reader needs to be charged.

*2. Make sure the reader is within range of the app.* The reader should be within about 30 feet of the app. If the reader is too far away, the app will not be able to connect to it.

*3. Make sure the reader is paired with the app.* You can pair the reader with the app by going to the Settings menu in the app and then selecting "RFID Reader." The app will scan for nearby readers and allow you to select the one you want to pair.

*4. Restart the app and the reader.* Sometimes, a simple restart can fix connection problems.

*5. Make sure the app is up to date.* The latest version of the app may have bug fixes that could resolve your connection issue.