According to your post history, you have not posted since January 31, 2018.  Therefore it appears that you did not post for at least 2 activity periods, and possibly you have not posted any for 3 activity periods.   You have to post at least 1 time every activity period in order to earn points for that activity period, and if you activity period passes without you making any posts, then you will not be able to make up activity points for that period.  

It is a "you snooze, you lose" sort of situation.