Usually, the salesman will collect the list of bank accounts from bank friends or acquaintances for telephone contact. There are also those bank employees who sell their customer contact information. It is also possible that you have logged into any website with your mobile phone and registered any information with your mobile phone. Every day, there are calls from the intelligent network to promote futures. Actually, I'm from a wealth management company, but I usually only call once. If customers are willing to listen to me, they will talk more. It's no use harassing them if they don't want to. I suggest you get a Baidu security housekeeper to block those numbers that often harass you.