Plateaus are normal. The usual causes are gradually eating more than you think, reduced daily movement, water retention from training or stress, and a genuinely lower calorie need at your new lighter bodyweight. Track honestly for two weeks before changing anything drastically.
Three or four weeks with no change in weekly average weight, waist measurement, or photographs is a plateau. Two weeks of a flat scale while your waist is still shrinking is not, and reacting to it usually makes things worse.
Before cutting calories, restore accuracy and activity. Weigh food for a week, count everything, and get your daily steps back to where they were. That alone resolves a large share of stalls without any further restriction.
Reduce intake by roughly 150 to 250 calories a day, or add activity of similar size, and hold it for two to three weeks. Small adjustments preserve training quality and are far easier to sustain than dramatic cuts.
If you have been in a deficit for several months, one to two weeks at maintenance often does more good than another cut. Hunger settles, training improves, and adherence recovers, all of which make the next phase more productive.
If weight loss has stopped despite consistent, accurately tracked effort over a long period, or you have other symptoms such as fatigue or changes in mood or menstrual cycle, it is worth discussing with your doctor.