I saw Li Lei yesterday.We hadn't seen each other since I left Beijing.
这句话没错啊.昨天已经见到了,所以没见过的状态只维持到昨天,所以要用hadn't.后面还有一句呢？您帮忙看看分析分析。。。。我说的是后面那句没错。你标题里那句是错的，haven't 应该改成hadn't，理由同上。