Diabetis type 2

I was doing really well with this , diagnosed 6 yrs apx ago ) , just a couple of metaformin a day , hbc 38

Suddenly gone to 59 , no change in weight , diet etc , diabetic nurse said it’s a progressive illness that will get worse , probably have to go on more medication if it continues in a sharp upwards trajectory

Any one had this , I just can see a reason for it suddenly worsening after 6 yrs of seeming to have it under control