I'm going to make my flatmate pay rent while she is overseas
Why does she have to pay when she's not there?
I'm going to trace her bank credit/debit card and she has to pay me back. She owes me money.
Your flatmate owes you rent, so she should pay. She shouldn't ditch the agreement just because she is overseas.
So she is allowed to leave the country and not pay me back? This is nonsense. I want my money.
How are you going to contact her about this other than the back? I agree that she shouldn't get off scot free, she still owns the property so it's still her responsibility. You don't deserve to be fronting the entire thing.