Why is it so hard to lose weight after baby?

So i gave birth to my 1st child in September of 2020.. i was about 125 pounds before pregnancy now i gained sooooo much weight throughout my pregnancy im at 165 pounds now.😥. I cant seem to lose it... idk why my pounds dont go low... i just love food i guess.. im trying herbalife and working out in the tridmil. I feel so heavy... i want to lose at least 20 pounds to be at like at least 140 . Someone help me