Messages keep disappearing/deleting on iPhone 14 Pro

Thanks for posting in the Apple Support Communities KingZoro,

As mentioned on the following page "If your device is low on storage, it automatically frees up space while installing an app, updating iOS or iPadOS, downloading music, recording videos, and more."

With that taken into consideration, checking to make sure there is ample storage space on the device is a logical step.

Use your device to check its storage

1: Go to Settings > General > [Device] Storage. You might see a list of recommendations for optimizing your device's storage, followed by a list of installed apps and the amount of storage each one uses.

2: Tap an app's name for more information about its storage. Cached data and temporary data might not be counted as usage.

In the detailed view you can:

• Offload the app, which frees up storage used by the app, but keeps its documents and data.

• Delete the app, which removes the app and its related data.

• Depending on the app, you might be able to delete some of its documents and data.

If your device is almost full and can't free up space, you might get a Storage Almost Full alert. If you see this alert, you should check the storage recommendations or you need to offload some less-used content like videos and apps.

You can find these steps along with other information you may find helpful, here: How to check the storage on your iPhone and iPad

Take care!