I don't understand how someone can be a আঁচিল in the FBI office like who are they communicating to?

yes i know who the আঁচিল is and i was totally shocked i just don't understand the sugar in the coffee thing

oh the sugar in the coffee thing was a signal to the other's she was working for, and they new this because she worked for them and they new she didnt have sugar in her coffee and she did it a few time's so they new it was the signal.