If your outdoor module's data is not displayed on the Netatmo dashboard, although indoor measurements are still visible, the link between the two modules might not be working. This may occur due to one of the following reasons:
Reason 1: Batteries are low
Check the outdoor module's batteries. When inserting batteries, the outdoor module should flash green. If you are unsure whether your batteries still work, replace them.
Reason 2: Weak radio signal
If the outdoor module is located too far away from the indoor module, or if both modules are separated by solid obstacles like concrete walls, data might not be transmitted correctly. In that case, make sure to move the two modules closer to each other.
Reason 3: Too close to the indoor module
If the outdoor module is too close to the indoor module (a few centimeters/inches) it may not operate properly.
Updated