Macbook force click no longer look up words in Safari

Hi I bought Macbook (2015) when it was released and I can't use look-up function in Safari with force click for few months.(I initially can use it)

• I use Safari, not Chrome
• Force click works just fine on any other applications (this indicates that it's not hardware malfunction)
• I am sure I give enough pressure on the trackback so I feel "2nd" click feedback
• Open preference -> trackpad and check "Look up & data detectors" enabled and choose "Force click with one finger"
• when changes to "Tap with three fingers", look up in safari works fine
• OS X updated to El captain, no luck
• Safari is also the latest build

anyone can help me?

thanks in advance.