To obtain an accurate position at least 4 satellites need to be visible by the device. Accuracy can be affected by signal reflections caused by high-rise buildings, weather conditions and a number of other factors.
Number of visible satellites can be seen on the device Configurator, under Status - GNSS Info.
Alternatively, you could send SMS message to the device to get this information.
Information on how to send the command -
Getinfo command to send and breakdown of the answer -