Four Months Ago As My A1C Was Still Holding Steady

Four months ago as my A1C was still holding steady at 2.8 by doctor changed my medication from 40 units Lanus once a day and 500 units metformin twice. Since this change my blood sugar is registering much higher around 135 and up as an average not including after meals My last A1C in January came back as 6.8 which is much higher.

Does it take a while until the new medication dosage of no Lanus but only 1000 metformin twice a day take a will to be effective?