Why is my husbands friend acting different?

So my husband recently has made a new friend (through my best friend) and of course they’ve been keeping in touch over the last couple of months. Well I finally got to meet him for the FIRST time this past weekend (we all went to a Halloween party together). All 4 of us got along great-no drama. But now he isn’t returning none of my husbands texts.. which is weird considering they’ve been texting for a while now. Any reason why he would switch up like that? I found it very odd.
Why is my husbands friend acting different?
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