case won't close with "official" Pi4 case fan

[cheddarpi]

I purchased the official Raspberry Pi 4 case (red and white) and the Official Raspberry Pi 4 Case Fan and Heatsink. When I install the fan, the case will not stay closed. When I snap the front of the case closed, it immediately pops open again. I can't see where the interference is occurring but it feels like the clear plastic shroud for the fan is pushing against either the RJ45 jack or the USB 3 jack. Did I get an "irregular" part or is it expected that the case will not close? I believe I have the shroud installed correctly in the top as shown in the photo.

If I remove the Raspberry Pi board from the case, it closes fine with the fan installed. So the issue appears to be some kind of interference with the board or its components.

[mikeysklar]

That heatsync looks too tall for this enclosure. Which part# is the silver heat sync you are using over the main chip?

This video might help showing more angles and describing assembly further.

https://youtu.be/mJtmQsptQvw

[cheddarpi]

Looking more closely at the heatsink was a great suggestion. It wasn't the CPU heatsink but a heatsink on what I think is the USB controller. (I inherited this Pi so didn't put the original heatsinks on) -- Anyway, thanks for the tip... problem solved after removing that second heatsink.