Going soft after head

Mary
Hi ladies i have a really weird question and i'm in need of some expertise.  Okay so every time i get down to business with my man and give him head he always going soft after he ejaculates and literally nothing makes it hard again.  I don't think it's a matter of me just not being good at it because he's always shaking and his eyes roll back and all that good shit and everyone i've ever given head to has said that i'm REALLY good so i don't think i'm bad at it.  Even he has said that it's not my fault and i'm really good.  But it's really starting to bug me because i want to do it for him but i also want to have sex after.  Is it possible that he's just not that attracted to me???  Has anyone ever had this problem before?  Thank u so much for ur help i appreciate it so much.