Should I make my husband change his number?

I’m a single mother of two boys 8 and 6 years old I met this man and I met this man a year ago, he is super nice and my kids loves his so much and he loves them so much too. As a single parent I always wanted to make sure that my kids are loved and they don’t feel like I got married and I never thought their well-being. But I made sure and we are all super happy. I got married last month and we are here on holidays.

So my Question is

My husband dated 4-5 women in the past and broke up. But they are always contacting him. But he doesn’t wanna talk to them and When I saw them contacting him I told them not to contact him. And he never said i shouldn’t say anything. when i asked him before marriage to change his phone number, he said they are all blocked. I don’t have to. But they do it from unknown numbers sometimes. I just couldn’t deal with that and I told him you have to change your phone number and he said he will not so I made this condition that if anyone ever will contact you again, you are going to change your phone nynevt and he said ok. So on new year his ex contacted him again and I asked him to change his phone number and he said he will. But my sister is here on holidays with us telling me I shouldn’t tell the girls anything and should just trust him and shouldn’t ask him to change his phone number this and that. I’m here and don’t even feel like speaking to anyone because someone contacted him today while we were driving to go for holidays, I don’t know if it’s right or wrong but I just don’t like any of his ex’s contacting him when we just got married it hasn’t even been a month. I had to get this off my chest so I can breath