No Reply from info email regarding Backendless T-shirt Milestone

I have finished the mission and sent the email to for free t-shirt since 6 days ago, but there is no reply until now. Do I need to wait or send the email again?

Hello @irwancheung

I will check if a letter came from you and if you still need to do something and let you know.

Hello @irwancheung

We received a letter from you, everything is fine.
Today we will place an order for a T-shirt for you.