You can raise an objection because you didn't notice it and the parties didn't know it. Companies need evidence to prove facts when dealing with workers.

If those who participate are counted as attendance, those who do not participate are not, and there is no penalty condition, the company has no problem. At the same time, things need to be viewed objectively. If all the workers are notified by WeChat, it's not good for you if you are the only one who didn't attend.