Hello harmn_104,
Thank you for reaching out to Apple Support Communities, and we'll be happy to help in any way we can. We understand you're having issues with iMessages sending as SMS messages. Try the steps here to see if they resolve the issue: If you can't send or receive messages on your iPhone or iPad - Apple Support
"If you see a green message bubble
If you see a green message bubble instead of a blue one, then that message was sent using MMS/SMS instead of iMessage. There are several reasons for this:
- The person that you sent the message to doesn't have an Apple device.
- iMessage is turned off on your device or on your recipient’s device. To check if iMessage is turned on for your device, go to Settings > Messages > iMessage.
- iMessage is temporarily unavailable on your device or on your recipient’s device.
- You might need to update your settings for Messages after you set up a new device.
Learn the difference between iMessage and MMS/SMS messages"
We hope this helps.
Cheers!