Hi lynx1312,
welcome to the Apple (user-to-user) Community!
Re: " In select group chats all of my messages are sending as a text message rather than an iMessage. "
Am no expert in this area, yet your question deserves some response.
Seems if your wi-fi signal is not strong at the time, and Wi-fi Assist is enabled, iMessages will go as SMS instead. More Info: About Wi-Fi Assist - Apple Support
You may want to check if the new iPhone has the newest available iOS version
About iOS 18 Updates - Apple Support says iOS 18.2.1
"This update provides important bug fixes and is recommended for all users".
(You can check in Settings > General > Software Updates) if you want.
NB: If you choose to update ... 'tis always wise to back-up your iPhone data first
Else if iOS is already up-to-date:
Restarting your iPhone will delete temporary files, re-establish connections, update recent setting changes, and will often restore order if something is not working as expected.
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Anyone else have this problem and find a solution?
Maybe someone with a similar experience can reply to this, now that your discussion thread is underway.
(As Apple users, like yourself, we never know what feedback / requests are sent directly to Apple.)
All the best :-)
