Why Is Rosinorm M Metformin A Banned Drug?

i am using rosinorm-m metformin for past i month. today i went to bought that medicine because my dr. told me to continue this. but i got the information that, that medicine was banned. i have cest. now i don't know wat to do. why this medicine is banned. m 27 year of age. trying to became pregnant. pls help me