If there is nothing in the environment that could be causing this, it is usually due to a blockage in the machines sensor port(s).
We suggest cleaning the sensors as per the ‘Cleaning the sensor’ article.
Further instructions on cleaning the machine can be found in the user guide and directly in the App under 'Using your machine' and then choosing 'Cleaning your machine'.
If this reading is still showing after cleaning the sensor and the machine, we’d suggest following the information in the 'Power Cycling/Restarting' your machine article.