Text messages don't work when my phone is offline.
Whenever I turn off my cell phone's data, or wifi, I lose the ability to receive texts from other iPhone users. I know of course, that iMessage uses wifi/data, and that iPhone to iPhone messages tend to be sent as iMessage first. I also know that there's an option in settings to send as text if iMessage is not turned on. AndI have updated my phone to the latest 17.2. My issue is that I don't always have access to data or wifi. If someone on android texts me, I receive it. If someone on iPhone texts me, I never get the text, nor a notification, until I am back online. I've asked friends to text me while my data/wifi were offline, then watched as I could continue the conversation on my MacBook and my friend's iPhone, but nothing appears on the iPhone. Once back online, I watch as the texts appear in real time, but back-dated as if they were received hours ago, all while receiving no notification.
In practice, this means I miss an extraordinary amount of texts from other iPhone users. Functionally, my iPhone is great as an iMessage machine, and near useless as a phone when not online.
I have called my service provider who claim it is an apple problem, apple who keeps telling me there's no problem, and taken to the Apple Store to have my phone reset, all to no avail. Has anyone experienced anything similar or have any advice? Any advice is greatly appreciated.