Airtime Use Question | 7-Eleven Rates and Plans | Consumer forum

Hi, this might be a silly question, but the past 2 months I notice my balance if going down 35cents each time i get a call but do not pick up. For spam calls, i just let it ring through and get to voicemail if the caller wishes to stay on the line. Now I am being charged for not picking up the call?

I recall in the past, not picking up isn't considered airtime use. Is this a new thing, and is anyone else experiencing this?