Hi, Krosen1210,
From your post, I understand that you are having trouble sending pictures via iMessage. Specifically, when you send one iMessage, you are unable to send another until the first one is finished sending. If you try to send additional pictures, your Messages app becomes unresponsive. Additionally, you’ve noticed another situation where the display will pop down halfway (Reachability) without prompt. I’m happy to help!
The first recommendation I have, if you have not already, is to force close the Messages app: How to force an app to quit - Apple Support. Then, restart your iPhone: Restart your iPhone, iPad, or iPod touch - Apple Support. This restart will address both iMessage and Reachability
If you have completed these two steps, in this order, and the issue with iMessage continues, the next step would be to check your connected network. If it’s private Wi-Fi, like at your house, reset the router if you’re able. This typically can be done by unplugging the router from power for a few seconds, but some routers also have a reset button. Check with your user manual or the manufacturer for the specific instructions.
If you’re on public Wi-Fi (or are otherwise unable to reset the connected Wi-Fi network), or you are using cellular data, try switching networks. You can go from Wi-Fi to cellular data or vice versa, and also try another Wi-Fi network.
In regard to Reachability, you can turn the feature off if restarting the iPhone has not helped, and you decide you do not wish to use the feature under Settings > General > Accessibility > Reachability. Switch the toggle from the on (green) position to the off (grey) position by tapping it.
Should you need additional help after trying these steps, do not hesitate to respond back. If you do, please confirm the iOS version number running on your iPhone 7. You can get that under Settings > General > About > Version.
Cheers!
