Hello @Angie59,
You have instant book selected. Do you also have additional requirements like "government ID" or "recommendation from other hosts" set?
Were you logged in when you searched on the other computer?
If you have those requirements set then you must be logged in when searching and your own profile must satisfy the requirements. Otherwise you'll not be shown instant book listings that have those requirements.
If you are not signed in when searching then Airbnb can't determine what requirements you satisfy and won't show you listings that have those ID or recommendations requirements.
If you are signed in but you yourself don't satisfy the requirement of having provided ID or having recommendations form other hosts then you also won't be shown instant book listings that have those requirements.
This is detailed in the response that @CarlandDiane0 got from Airbnb.
https://community.airbnb.com/t5/Hosts/Instant-Book-is-on-but-doesn-t-appear-as-such-in-searches/m-p/...
Steve.