Telegram settings should be set so that only your contacts can message you or call you or add you to groups. For me, that latter two are set, the former not. I am on an ICE3X* discussion group, and a number of people started spam conversations trying to get me to sign up at some or other bitcoin website. I played with one such person for a few days. I finally got her to agree to marry me, and then I blocked her. Relationships like that can’t continue forever.