Hello all – I am not an IoT specialist but rather a biologist so please bear with me. I am working on a project using small GPS trackers that use 2G wireless to transmit information on either GPS fixes or LBS data based on tower connections to a web platform to track locations. The little transmitters are rather primitive and must be initially programmed via SMS messaging with the correct APN in order to transmit data to the web platform
We have been successfully using Hologram Indigo SIM cards for some time, and the last time I set up and programmed several in June 2021, all was working fine. Once the APN was set to hologram, they would transmit data fine. If the APN was not set to hologram, they would connect and I could query them to send locations via SMS messaging, but the locations would not update on the website.
I am now trying to set up a bunch of these to go out to the field, and I am not able to get them to connect to the web platform, they instead act like the APN is not set to hologram – i.e., communications via SMS only, not via data. This is the case even for transmitters and SIM cards that were functioning perfectly in June 2021: even though I could track them through the web platform a few months ago, the same transmitter with the same SIM card is no longer sending data to the web platform.
I have not updated any firmware on these guys, they were fine a few months ago when last used, and are now acting as though they do not have the APN correctly set. I am still able to use SMS messaging, which is not ideal because of the per SMS fees.
I’ve been trying to get help from customer support without a lot of progress. The customer support tech I have been in contact with told me that the APN for the Indigo cards should be indigo (something that I have not seen in any of the documentation!) but even with reprogramming the trackers are not connecting to the internet. I’ve tried also setting the APN to T Mobile and ATT APNs (since those are the networks they are connecting to in my area), but I’m not getting any results from that either.
Anyone have any thoughts on why the Indigo cards might not be functioning anymore with the trackers? I haven’t updated the firmware, and aside from changing the APN settings a bunch of times I haven’t changed their programming. The manufacturer of the tracker says that their web platform and smartphone apps are working (I unfortunately do not have another 2G-capable SIM card handy to confirm). Any strategies I might try before we have to resort to SMS-exclusive communication with the trackers?
Thanks in advance.