@Linda3820
Personally I would not pester a guest for a review, the problem is as I see it you already have a guest book which as you say they have left a message there, to me it defeats the object, I dont have one.
Airbnb remind them 3 or 4 times to leave a review they dont need you to be asking,
I have heard some host say you leave a review right away or as soon as you can prompts the guest to reply as they want to know what you have said, you could try that way.
I ask them once when they are leaving and thats it, they either do or they dont, not much we can do.