First, congrats on the weight you already dropped ..
Your caloric intake is either way too low and your body has kicked into starvation mode (vegetarian diet?) or your calorie/exercise ratio is balanced and your going to need to change one or both to get the weight loss to continue ..
Start with Changing your workout .. Frequency, number of reps, order of the routine .. Days you workout .. Any or all of that ..
would need alot more info to be able to give any more specific advise .. Current routine/diet .. Stats ..