We have a sensor connected to a nb-iot board. I set it up using the tutorial to send the readings to a google script someone else wrote for us. It worked fine for a month, but two days ago we started receiving messages with nonsensical values approximately every 20 seconds. I deleted the subscription using Postman and registered another one, but the same thing happened. Now I did that again with the nb-iot device powered off. The device has now power, but I am still receiving the nonsense data. I’m not even sure where to start looking for the problem, do you have any suggestions?