Q: seen doing last update battery life has dropped.will only last 2-3hr after fully charged

First, billt7462, welcome to Apple Support Communities!

While battery issues can be difficult to pinpoint, here are some areas you can check to maximize your iPhone's battery life: Maximizing Battery Life and Lifespan

There's also a way you can find which app on your iPhone is using the most. About the battery usage on your iPhone, iPad, and iPod touch You can view the last 24 hours and the last 6 days. 

If you updated your iPhone through the phone itself using Settings > General  > Software Update, restoring your iPhone will make sure the iOS was installed correctly. 

Since this process will completely remove everything from your phone, it's highly recommended to be sure to have a recent back up. Back up your data

I'd also recommend that you to transfer your iTunes & App Store purchases: Redownload or transfer your iTunes Store purchases from an iPhone, iPad, or iPod to a computer

Another step would be to import your photos and videos. Import photos and videos from your iPhone, iPad, or iPod touch

Once all of your information is safe, you can erase your iPhone and set it up as a new device. How to erase your iOS device and then set it up as a new device or restore it from backups  When your iPhone starts back up, this first time through, skip restoring your phone from the back up you've made and set up as new instead. Test your battery life for a bit to see if it's improved.

If it has, you can use this article to help you restore your back up: Restore your device from an iCloud or iTunes backup

After following those steps and recommendations your battery life is still short, the problem may be in the data you've restored from your backup.

Take care!