1680 Bezel won't fit in

[llm3000]

Hi Guys, I recently purchased a 1680 red sub with Mk IV Dial. it comes with a service bezel insert, so i added a bit more to buy a Rolex MK 3 insert from the same seller. However, it can't be tuck in. i had some other 1675 or 1680 and this never happened before even with the aftermarket ones just for the look

The measurement i got for the MK3 insert is 36.52mm dia. and the service insert is 36.34mm, the service insert can be securely tuck in with my fingers and do stay there. But the Mk3 looks like it is a tag bigger and i don't feel like it will go in even with the help of a piler or wood stick, it will slightly pop up after all areas are tucked in.

Seller is kind and happy to refund and take the bezel insert back or change another one for me but i am just curious. I asked a friend to measure his red sub bezel insert, the number is also 36.5mm.

Any experience, idea or suggestion? Cheers! *NEVERMIND IF YOU DONT HAVE SUGGESTION, NO NEED TO TELL ME TO RETURN IT. THANKS!