iPhone is not updating Active Energy after unpairing Apple Watch

The scenario you describe seems to be related to how the "Move" and "Active Energy" metrics function in the Health app, and not necessarily a malfunction.

Here's a breakdown:

• Move: This metric specifically tracks calories burned through physical movement detected by your Apple Watch. Activities like walking, running, swimming, etc., contribute to the Move ring.
• Active Energy: This metric represents a broader picture of your daily energy expenditure, including both movement-based activities and basal metabolic rate (BMR), which is the number of calories your body burns at rest.

Fitness app fetches the Resting energy from the health App. If you do not want them you may delete them. See the pics below

There is nothing to become paranoid about this. If you are measuring the Active Energy then you ought to know the Resting Energy too.

However, your may read below to understand what it means for you.

Total Energy used by your body = Resting Energy + Active Energy: You may get more insight into the Total Energy --> Energy Consumption Of The Human Body - Stanford University

Resting Energy

This is an estimate of the energy your body uses each day while minimally active. Additional physical activity requires more energy over and above Resting Energy (see Active Energy).

Active Energy

This is an estimate of energy burned over and above your Resting Energy use (Resting Energy). Active Energy includes activities such as strolling, pushing your wheelchair, and household chores, as well as exercises such as cycling and dancing. Your total energy use is the sum of your Resting Energy and Active Energy. 

Here's why your "Active Energy" might be lower than "Move":

1. Workout Tracking: If your Apple Watch wasn't actively recording your workout (due to being locked or not recognizing the activity type), the "Move" wouldn't reflect those calories. However, the imported data from Strava might still show up in the "Workouts" section.
2. Active Energy vs. Total Calories: "Active Energy" doesn't directly translate to total calories burned, as it includes BMR. So, even though you burned calories during the workout, the "Active Energy" might not reflect the full amount if it's already accounted for in your BMR.

Tap on Show all Health Data

Total 1,990 Cal (Shown in the Pic posted by you) = Active Energy + Resting Energy (From the Health App)

An example from my iPhone given below

Here are some suggestions:

• Ensure accurate workout tracking: Start your workout session on your Apple Watch for a more accurate reflection in both "Move" and "Active Energy."