Hello! My name is ***** ***** I'll be assisting you with this issue.
First, make sure you clear all apps, photos, and documents that you don't want.
THEN, do a hard reset by holding the POWER and HOME video until the Apple logo appears and then disappears.
Some apps like to hold on to memory that they shouldn't, and a hard reset should resolve that.
Also, turning off iCloud photo helps if you don't use it.
You may have to do a hard reset occasionally, especially if you do a lot of streaming on your phone. This is a glitch that happens sometimes in the iPhone 6. I'm sure it will be fixed in a future update.
If you have any questions, please reply back. If this resolves your issue, please rate my answer with at least 3 stars!
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