Hi Piotrek,
Thanks for your quick reply.
I tried to disable one or both, but found it still the same.

But later I found this odd thing:
When it is the first facebook comment on the post, it will show the “more than one OG URL specified” message. But when it comes to the second, the third, and more, the message would not appear any more, and the comment just showed right away.

Is there any explaination for that?