BLU C5L missing 2.72Gb of "storage"

BLU C5L only showing 5.28 of 8.0Gb storage. This phone has 8Gb internal storage. When opened to analyze ‘storage”,“it showed 5.28Gb as total storage. Missing some 2.72 Gb? I would guess the missing 2.72 could be Android 8.1 O.S., but then it should show 8Gb available minus the O.S. and apps/files. Somethings not right. It should show 8Gb to begin with, then show what the O.S., apps and files are using, and then show “available”. It shouldn’t be a “max” of 5.28gb available. Ran “STORAGE AND DISC ANALYZER” it also showed 5.28Gb. Long story short; missing some 2.72Gb of SDD(phone’s) “storage”.