Hi
How do you know you have a duplicated workflow? HOw do you know your flow isn't simply triggering twice? If it was "duplicated" it would have to have another name.
Do you have another Version running in Dev or Test and pointing to the wrong place?
Also, when you LOOK at the Details Page of your Flow, do you see it triggering twice????
Lastly, go to the Details Page, select the see all runs (in the corner above the runs at the bottom)
Once there, Filter (on the top right) to see any flows running and make sure you dont have any Ghost instances running.
To find it do this. (if its online)
1. Go to Power Apps Home
2. Go to the Unmanaged Solutions Tab
3. Open the Default Solution
4. GO to the Cloud Flows
Look and see if you see any weird, or rogue copies of your flow
Those are the answers above, one of them is what you are doing. Go through slowly each thing I said. Either you are doing it, or someone else has a copy running somewhere.
