I've change my password 3 times cus someone ...

I've change my password 3 times cus someone log in my account these few days:(
this is what i saw by Facebook msg :
　
Your account was recently accessed from a location we're not familiar with. Please review the activity details below:
Near Warminster, PA, US (Yesterday at 18:25) from Chrome for Win7
　
因為有人登入我的帳號，索以我在這兩天已經換了三次的密碼了:(

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