What version of NSX are u using.
In my environment i am using version 6.2.2 & I have faced similar problem.
The ping using CLI by vmkping is fine & it gives the desired outoput. But some times via GUI it does not reflect the right out.
Since the VMKPING is giving the right output, your setting are right & there will be no impact.
This could be related to some display issue. I have not escalated this with VMware since it didn't affect my production.
Thank you for your suggestion Rajeev
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