Unable to send picture messages on my new iPhone 18 Pro

I just updated to an iPhone 18 Pro and now I can’t send any pictures by text message. When I try, the picture shows up in the text message and a blur bar appears under the picture and slowly extends for over a minute and then says failed to send. I have tried toggling airplane mode, WiFi, shut the phone off and on. Any ideas?

[Re-Titled by Moderator]

Original Title: Can’t text pictures.