How do I fix iPhone storage not loading?

Did you already try to force restart the phone? You will not lose data, but this can cure some glitches.

• On an iPhone X, iPhone 8, or iPhone 8 Plus: Press and quickly release the Volume Up button. Press and quickly release the Volume Down button. Then, press and hold the Side button until you see the Apple logo.
• On an iPhone 7 or iPhone 7 Plus: Press and hold both the Side and Volume Down buttons for at least 10 seconds, until you see the Apple logo.
• On an iPhone 6s and earlier, iPad, or iPod touch: Press and hold both the Home and the Top (or Side) buttons for at least 10 seconds, until you see the Apple logo.

Updating to iOS 11.4 might also be necessary, in case this does not work.

An encrypted backup made in iTunes before you start, will also contain the password for your Wi-Fi and other accounts.

Restore your iPhone, iPad or iPod touch to factory settings

Yes, I ended up having to restore my iPhone to factory settings but that has fixed the issue. Here is the link on how to restore your iPhone to factory settings:

https://support.apple.com/en-gb/HT201252

Don’t forget to make a back up first because this literally erases everything so your phone is like brand new!

I’m having the exact same problem. Did you ever work out how to fix this? Thanks

Did u ended up finding a way to fix this ?