Stopped losing weight

Hey guys, I’m 7 weeks pp and my weight loss has completely stalled. I’m breastfeeding and have been eating healthy but nothing has been happening. What are you ladies doing to drop the weight? I weighed 190 when I gave birth and I’m 172 right now. I was 165 before but need to be 145 (I had two ectopics and 1 miscarriage prior to this baby and put on the weight.) I also have lupus and can’t do a ton of cardio because it will make me flare. Suggestions??