It seems that this is just your imagination. Because you have no evidence to prove that little sister is the girl who occupies the position in your fitness card.

I don't know how your fitness card is stipulated. If there is a time limit, you can find it completely. If there are no restrictions, it seems that even if others use your card, you will not suffer. The former can be held accountable if there is an answer, while the latter seems to have no answer and I don't know where your entanglement comes from.

For example, if you spend 10 thousand yuan on an annual card, then whether you go or not or go every day in this year is within the scope of this card. If someone uses your card number to bring more people in at this time, and it is the gym that suffers instead of you, what do you regret?