Here are the steps to remove the add-in globally from all your users.
1️⃣ Go to the Microsoft 365 admin center
2️⃣ Integrated Apps
On the left menu: Show all > Settings > Integrated Apps
3️⃣ Click on the Add-in
4️⃣ Remove the application
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Then check the validation box, then delete
If you were unable to follow these steps, here is a gif to summarize the procedure to follow.
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