Not losing despite calorie deficit

Hi! I (24F) am trying to lose 20-30 pounds. I have hashimotos and type 1 diabetes as of recently so I’m wondering if that’s part of my issue but I’m having a hard time losing weight. I was previously using weight loss meds but not working out and got down to 155 but since being diagnosed with T1D a few months ago I stopped taking it and have switched to calorie deficit and exercise. I eat 1500 cals a day except for weekends where I don’t track but I’m not like binging or going crazy, just not being super strict and I work out consistently 5-7 days a week. I lift and do cardio. Despite this I have actually gained weight and am approaching 170 again. I’m not sure what I’m doing wrong and I highly doubt it’s just muscle that I’m gaining because I’ve only been lifting again for 3 months. I don’t felt like I look bigger and my clothes are still fitting me similarly to when I was 155 so I’m not really sure what’s going on here. Advice appreciated!