Holly1295,
I experienced the same issue, but it took me 6 months to get an appointment with an endocrinologist. I never had an issue with belly fat, even after menopause, but everything changed when I got Covid. Suddenly I weighed more, and no amount of dieting helped. The majority of the weight was in my belly and breasts(I went up 3 cup sizes) . I sought help first from my PC, she told me to exercise more. Next I went to a gastroenterologist and she told me I was constipated. I requested a SIBO test, that came back negative. Finally it was time for my endocrinologist appointment and someone listened to me. Turns out that my cortisol level was high and was a possible explanation for the weight gain in my stomach. Hope this information helps.
https://www.medicalnewstoday.com/articles/hormonal-belly#cortisol