Why do I not receive text messages?

I have switched phones from having an iPhone and my inactive iPhone still receives messages from other iPhones as iMessage texts. I turned off my Imessage in the settings on my iPhone but I still do not get texts on my new phone from iPhones…

Try restarting phone

  • Why don't I receive alerts or a notification when I receive a text and I already checked my settings? I adjusted my setting and even put the ringer and notifications on and put the volume and ringer on and I receive no alert, no pop up, alert or notification when someone texts me. Why? This is the iPhone X! I went to the cell phone/ carrier store and they didn't help me. They said to go to the apple store or check the settings. I already adjusted the settings. So what do I do now?
  • Why does my iphone5 receive text messages twice? When my iphone5 is on the lock screen and I receive text messages, unless I respond or look at it right away I will receive the same text message a minute later. Does this happen to everyone? How can I turn this off? It's very annoying!
  • Why does my iPhone receive messages late when I'm in a group text? I have the iPhone 4s with 16g (I have less than a gig left of space) and am on T-Mobile. Every single time I'm added to a new group text, my phone delays all messages sent to me. Regardless of whether it's another iPhone or if they're on the same carrier as me, none of my messages get to me until an hour or so later. Is it because I'm low on space? Or is it T-Mobile (probably the worst carrier I've ever had by the way)? Or is it the iPhone software?
  • Why do people with iPhones receive email text messages? I have an iPhone and other people I text with iPhones tell why when I text them they get my email instead of my phone number. Why is that is it possible to not to ever send out my email just my number. When I text them with my iPhone.