I have not been able to get LTE data capability while on roaming networks on my Librem 5. This has been the case in my native US and now while on vacation in Europe.
In the US I was using the BM818-A1 modem and here in Italy I swapped it out with a BM818-E1. The service in US was T-Mobile which works very well while in-network. In Europe (Italy) with my E1 modem I see I am connected to Wind Tre and I have updated my APN settings according to their website. Regular sms works and calls work, but no data and I have the orange exclamation mark on my 4G symbol.
I have enabled mobile data and data while roaming in my mobile settings and I’m sure my APN is right.
I also purchased and got confirmation that my telco service international support knows I’m here and roaming through a text message when I powered on my phone when I arrived on the plane.
Any tips? I saw in the forum here Wind Tre had support for the Librem 5.
I was able to get mobile data fine when roaming in Argentina with my Indian SIM (Airtel). I did not have to change the APN. I continued to use Airtel’s APN. I suggest you try with your home providers APN. This worked in transit too - Qatar and Brazil airports.
Sometimes, I had to restart the phone to get data working, I think the problem happens when it suspends and wake up. I’m on crimson.
Even *99# USSD based payments worked fine on roaming. Calls worked fine too. Did not try SMS.
Well, turns out in fact that all along I had the wrong APN for my home provider. Not sure how it as been working at home for years. Once I looked up the correct settings it all started to work. Data, mms, all of it. Thank you @praveen.arimbrathodi !