Friend has an iPhone 6s, 64GB currently saying there is no storage available, even though there clearly should be. Also looked up & saw it isn't unique to him. Deleting things still result in an Available storage of 0 bytes.
Plugged into iTunes?
Bet it's "Other" storage that's taken the space!
what does iTunes say about space when you plug the phone in?
checking that now.
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Reporting the correct amount of free space, in this case is ~34.13GB. Phone now reflects this.
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Wouldn't count it to be just a display issue though since apps acted accordingly to what was being reported e.g.