# No contact with Boomerang 3

If there is no contact with Boomerang 3 server when the app communicates with it, “PENDING” and “TIMEOUT” are shown in the B3 status line. The app communicates with B3 when:

* MP shall be selected for calibration which reads a list of measuring points from the server,
* the app reads B3 measurements or sends the adjustment and certificate to B3 server during [finalise-calibration](https://help.boomerang3.com/boomerang-3-calibration-app-manual/performing-the-calibration/finalise-calibration "mention"),
* [discard-calibration](https://help.boomerang3.com/boomerang-3-calibration-app-manual/performing-the-calibration/discard-calibration "mention") or [recalibrate](https://help.boomerang3.com/boomerang-3-calibration-app-manual/performing-the-calibration/recalibrate "mention") is selected.

In such a case:

* log out and log in again,
* check your Internet connection.