There can be a couple of reasons why the sensors are transmitting the data slowly. We are listing some cases here which can give you guidance to some extent on what could be the issue:

• The sensors are very far away from the gateway or else can only connect sporadically due to a poor/instable connection. -> In this case, try moving the sensors and/or the gateway closer to each other and see if that helps.
• The LoRaWAN protocol can sometimes have hyper local implications on the transmission. It can therefore take some time for the sensor to accustom itself to a new location. Else, it might take some time (up to a few days) to establish a good connection to the nearest gateway. 

For the case that the sensor cannot establish a connection to the nearest gateway for sometime, we have specifically assigned a memory card to each sensor to save the data up to 6 months at most. Once the sensor can establish a connection again, it will "dump" its data and erase it from the memory. 

If you have further questions concerning this issue, please reach out to us at [email protected] and we will be happy to take a look at your individual case.