By Transaction stands that I got 3 but when I open Instagram I only got 1. I try it out the bug is that you dont have to follow somebody by instagram to earn credits. You can leave Instagram without follow the person and you will get credits.
no - there is no bug.
If you unfollow or don't follow the credits will be deducted afterwords.
However - every statistic about 3 followers will not be very representitive.
The statistic about 100 followers will be nearer to the real counters.