Is your DSN aware of the severe hypos?
Is there any pattern to when they are happening - if it's 2 or 3 hours after eating & your bolus that suggests you ratio needs adjusting down. If they are more random, it could be your basal dose is too high.
If you are not hypo aware and you are having frequent severe unconscious hypos, the advice is to try to run higher (ie stay over 6) and test frequently.
I would also look into a CGM that keeps a constant eye on your blood sugar and alarms if you are dropping low- they are expensive though.