Please answer my question!

Hey there! So far I have noticed that each new day you log in, you will get the next day's rewards, even if you skip days inbetween. So if you log in Sunday for the Day 2 rewards, then log in today, you should get the Day 3 rewards. I assume there is some time in the future that they will go away, and I don't know if you can get them after that day (I assume not). Daily reward missions expire in 4 weeks, so maybe that is the cut-off day. Hope this helps answer your question!

You don't miss them. So far. Each mission shows a deadline, in your mission tab. You don't actually need to do them daily. You can log into an account right now, play 5 matches in a row, and get the first 5.