@joannaspanner Things that folks need to know to answer this question for you:
Are you still tracking your food/Protein/Etc?
How many calories are you consuming?
Are you still tracking your water intake?
How much water are you consuming?
Are you exercising?
How often?
How much?
Cardio only or Cardio and Weight lifting?
Somethings to consider.
As we lose weight and get older, our BMR (Basal Metabolic Rate) decreases. BMR is the amount of calories you need to exist, think in a coma, alive but not moving. You can check yours here https://www.active.com/fitness/calculators/bmr
As we get older and lose weight we need less calories, which means we need to either exercise more, or consume less. If you aren't tracking... start tracking again. The math is pretty simple, If you burn more calories than you consume, you'll lose weight.
Water intake, our bodies cannot process fat if we don't have enough water to do so. So if you aren't tracking your water or aren't getting 64-128oz of water, start tracking and increase.
Daily movement at work etc is great, but it's not really enough for weight loss, you should be in the gym at least an hour a day. And that brings me to muscle mass. Larger muscles burn more calories than smaller ones, so if you build some muscle, you will burn more calories the rest of the day than you would without larger muscles.