My hgb is 12.3 and the system states it's not in a normal range? why? hgb

Hard to be sure: The hemoglobin assessment is done with automated equipment that usually reports out vales in a range from lower to higher. Each lab or equipment will have their own accepted normal range. I would not consider your hemoglobin value much of an issue, although it is at the lower end. It may suggest blood loss over time or dietary deficiency of the iron needed to make it. Discuss with your doc.

Depends: If you are a woman, it is normal. If you are a man, it is lower than normal and the cause needs to be established. Low HGB in an adult male warrants that bleeding in intestine be excluded. Talk to the doctor who ordered the test.