Need some help with my Duncan

[Fasthackem]

Not sure if I've got a Porsche or a lemon.
My Duncan has been fully closed to partially open for four months. It's not showing any signs of flesh damage anywhere, and it's splitting like crazy. At least 60 heads. I probably shouldn't be complaining. Has anyone else experienced anything like this? Will it ever stop splitting and fully open?

Thanks in advance
F-

 

[Fasthackem]

Here's a picture

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[bkstang]

Duncans are very sensitive when bothered by shrimps or crabs. Did you observe this in your tank. My duncan stayed closed for hours when it was bothered by shrimps especially Peppermint shrimps but other than that it was huge and finally I had to sell it because it started to touch other corals nearby.