The same procurement agency has two bid opening activities on the same day, but the bid evaluation experts are the same. Is this a violation?

It's not illegal. If you are a bidder, you should know that even the comprehensive scoring method has its own default. Don't question anything, even if you do, there is absolutely no room for turning around. All you have to do is get on well with your host. I hope to invite our company to the next tender or inform us in advance before the public tender. I hope you win the bid next time.