Eating too many carbs
One of the main reasons why you can't lose weight on the keto diet is because you consume too many carbs. To reach ketosis, a metabolic state in which the body burns fat for energy instead of glucose, carb intake must drop drastically. In fact, only about 5% of the total calories in a meal should come from carbs. This is in stark contrast to the standard dietary recommendation that for the average person 45-60% of calories should come from carbs. However, to achieve and maintain ketosis, the carbs must be reduced to the recommended range.
Most processed goods include hidden sugar and refined carbohydrates, as you can see from the ingredients list. On a ketogenic diet, this is disastrous, so if you're not checking every nutrition information label, you're definitely consuming more carbs than you think. To make sure you're not consuming too many carbohydrates by accident, learn all the names sugar goes by (maltodextrin, rice syrup, and fruit concentrates are a few examples).