I recently upgraded my 12yr old 3g mobile phone with a new 5g/4g Samsung A13. I also upgraded my wife's 3g phone as well to the Samsung A13. We swapped the SIMS from the old phone to the new phone, after trimming them to fit the Nano SIM slot. The phones have since worked perfectly to send texts and voice calls. The reason for the upgrade was that the US carriers no longer operate using 3g and require 4g/LTE/5g devices.
We both have US Roam Ready on our account and have used our old phones in the past while in the States, without any issue at all.
This past week when we went to Tennessee on vacation. The phones worked normally up until we crossed into the US. Once the phones started to roam on either T-Mobile or AT&T, texting became intermittent. Both phones would either have to be restarted, or the Airplane mode would have to be turned on then off, to get the phones to send or receive text messages. This solution would only work for 2-3hrs, or if we moved locations, then the phones would have to be reset again.
I tried changing multiple phone settings to determine what was going on, but was unsuccessful.
When we drove back to Canada, the minute we crossed the bridge the phones started working normally again.
I am now wondering if the 12yr old 3g SIM card from our original phones is causing issues connecting to the US networks since they do not support 3g anymore. A Google search says that the SIM cards may or may not be interchangeable, so I am unsure if this is the issue. I may order two new Telus LTE SIMS and see if that fixes the problem.
Has anyone else had this issue ?
