How long has it been since your baby was born?
I felt the same way after my daughter was born, like the weight was just not coming off. But it did, it just came off really slowly. But I've learned that the weight that comes off quickly, goes back on quickly - the weight that comes off slowly, goes back on slowly. So losing weight ofver time is actually better.
It took me almost a year to get back to my pre-pregnancy weight, but I attribute all of the weight loss to breastfeeding. I rarely exercised

and ate pretty healthy, but did over do the sweets. And I still lost the weight. Thank you breastfeeding!
I definitely suggest keeping up the exercise, besides losing weight, it is always benefitial to your health. But if it hasn't been that long since the birth of your child, it may just be a matter of patience.