17.1.1 update installed but not enough storage

There are a couple of things you can try.

Try freeing up space on your phone -

How to check the storage on your iPhone and iPad - Apple Support

Manage your photo storage - Apple Support

Clear Other storage on your iPhone or iPad - Apple Support

Use a computer to upgrade, it requires less space on your phone this way -

Update using your computer -

Update iOS on iPhone - Apple Support

vibhabesagi Said:

"17.1.1 update installed but not enough storage: [...]Now, I have the iOS 17 previous update taking up storage and the new one so iOS takes up 15 GB of my storage, I only have 64 GB. I can’t send or receive a lot of messages or it just crashes. Please help."

-------

Clear Internal Storage...

Troubleshooting iPhone Storage:

Internal storage cannot be upgraded. It is what it is. So, the maximum internal storage capacity never increases, even if you upgraded your iCloud plan. Learn More here: What's the Difference Between Device Storage and iCloud Storage? Apple Support

So, what to do...

Clear Space Using my User Tips:

• How to Clear Space from your Mobile Device, and What to Clear: - User Tip. You may have too much installed, and need to clear space. So, see my user tip: 
• How to Clear "Other" in your iPhone's Storage - Use Backup - User Tip. Caches would be being used for remembrance of application use. It is essentially the same for an iPhone. You'd backup your iPhone, and then restore your iPhone from the backup you've just created. All System Data will delete.