Can he contact his (female) cousin to greet her by phone?

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Check below answers in case you are looking for other related questions:
He wants to talk to a girl without saying anything improper
His friend got to know a woman; can he call her to ask her to keep away from him?

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Related Answers:
Etiquette of talking to women
Ruling on a woman talking to the tailor
 He speaks improperly with a woman, with the excuse that he is teaching her
He wants to talk to a girl without saying anything improper
His friend got to know a woman; can he call her to ask her to keep away from him?

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