Is it okay that my boyfriend is hanging out with girls that he used to hook up with?

The question is pretty self explanatory but my boyfriend who is in another state is hanging with girls who he used to hook up with. These girls are prettier and I am slightly insecure we have been together for almost four months and he calls me every day always counting down til he sees me...i mean I shouldn't be worried but he hangs with them its different if he was talking on the phone...
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+1 y
So I am going to put it out there that I trust my boyfriend but I am just uncomfortable and I am going to tell him that..
Is it okay that my boyfriend is hanging out with girls that he used to hook up with?
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