に限って

に限って is used to express a strong exception or contrast: something is unusually or especially true for a particular person, thing, or situation, often implying disappointment or surprise when the expected norm is violated. It can indicate that a negative event or an undesirable outcome is especially likely to occur to that specific subject, or that something is true only under that narrow condition. Common contexts include complaints about misfortune happening to a specific person, or stating that a particular circumstance is uniquely true for a certain group or person.