This can happen when you have the Smart Macros setting enabled. With Smart Macros, this is normal functionality.
The Smart Macros setting (in Settings > Macros), tells the app to automatically recalculate your goals on a continuous basis based on your profile, current weight, and macros ratios.
With this setting enabled, your goals may vary day-to-day and won't exactly match what you've entered in Settings > Diet Goals because Smart Macros automatically adjusts the goals based on changes logged during the week.
For example, if you've set up a weight goal to lose 1 lb per week, once you meet your weight goal, Smart Macros will switch you over to maintenance mode, which may significantly increase your macros goals and your calorie budget.
If you'd prefer to set static macros goals, you can turn off Smart Macros under Settings > Macros.