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"I want reach 7 percent as A1C after 3 months exactly. Now my A1C is 8.9". The only way to lower your A1c is to lower your blood glucose average. Your current BG average is ~209 mg/dl or 11.6 mmol/l. In order to reach your goal of 7%, you will need to get your BG average down to ~155 mg/dl or 8.6 mmol/l.
In order to accomplish this goal, you may need to adjust your food intake, exercise routine and insulin dosage. Test often and good luck.