A common cause for missing data on an SDI12 input is an issue with the physical connection/wiring of the sensor to the Outpost logger. In this scenario it's possible the sensor may still be reading data but cannot 'see' the logger therefore no data is getting saved or uploaded.
The easiest way to determine if this is the case is to check the event log - the blue flag icon on the right of your login under the Tools column.
Entries like this (below) are typical of this issue and would indicate a site visit may be required to assess if the sensor is working and powering up, if the connectors are still water-tight, and if the wiring from the sensor to the logger is not compromised.
