I have an 18 month old staff and recently she has started poking in her crate at night and when ever me or my partner go out the house, she gets 4 walks a day so it's not as if she's not getting out

Other than that she is the perfect dog loves people, kids other animals is obedient but nothing I do is kicking her out of this habit and it's really starting to cause arguments between me and my partner and I will not get rid of my dog so I really need help with this

Thank you for any help you can give

What is poking?