As I’ve tried to explain, if you load a “plain number” into a Quantity type Item, it will assume that Items default unit.
So set default “b”, post “22”, get “22 b”.
Set default “Gb”, post the same 22, get “22 Gb”.
Obviously if you post a plain number you must set Item default to the units the number is really coming in.
That’s fine, it works.
But it leaves you unable to show the value in Gb - the default unit is used for for both purposes and can only be one thing at a time.
If you post the full “22 b” (e.g. by using a profile) it doesn’t matter what the Item’s default units are, auto-conversion works.