Why can I not send green texts on my iphone5S sometimes? I just get the red exclamation mark and undelivered. Very frustrating!
Best answer by Ryan
When you mention that it only happens with certain numbers, with those numbers, does it happen with every text you try to send to them? Also when that happens, do you still have a network signal? The green messages would indicate that they are not being sent via iMessage as you mention, so there could be a signal issue.
It might be worth trying the below iMessage steps anyway, just in case this helps the situation by refreshing the phones settings:
1) Turn off iMessage (Settings > Messages)
2) Restart your phone (by pressing and holding the on/off button)
3) Tap Settings > Phone > My Number and confirm that it is correct.
4) If it is not correct, please enter the correct number
5) Turn iMessage back to On (Settings > Messages)
6) Finally, go to Settings > Messages > Send & Receive and see if the correct number is displayed under “Start new conversations from:”.
Please let us know how it goes.