A1C has increased

I was diagnosed a year ago with an A1C of 9.4. I had gestational diabetes in 3 of 4 pregnancies. My two previous
A1C stayed at 9.4, but was up to 12.4 yesterday. I have lost 48 lbs and follow the diet relatively closely. My dr. said I was toxic…..get better control and document every reading, uped my meds…..what exactly does toxic mean?