Apparently I don't know how to communicate effectively

C: I want an ice cream.

Me: Do you want a cone like S? With chocolate and vanilla?

C: Just chocolate.

Me: Just chocolate, no vanilla?

C: No vanilla.

Me: (Made an ice cream cone and brought it to C.)

C: Huh? (unhappily looking at the chocolate ice cream) I wanted all vanilla.

Me: You said just chocolate.

C: No.

Me: I'll put that one away and make you a vanilla one.

C: Okay (handing me the cone).

Me: (Put old ice cream in the freezer, made a new ice cream cone and brought it to C.)

C: (Took vanilla ice cream with no complaint)

Me: (Wandered off wondering how I manage to have these completely mixed up unproductive conversations.)