Is my grammar correct?

[Anonymous]

Hello,

I just want to let you know that these past few weeks I have noticed / or I noticed that there's improvement to each one of you. More people talking, more people helping to build flags. I am just glad that there's a changes in this alliance. Lets do our best to powerup, lets participate more in activities. Keep up the good work and keep powering up.

[Wise4myage]

Not sure what you mean by building flags, but the rest sounds perfect.

[Asker]

Is it I have noticed or I noticed?

[Wise4myage]

I have noticed.

[Asker]

Thank u. About building flags its about the game Rise of Kingdom. And I have to send mail in that game.