You can get up to 1000 contacts per request, I think there is no way to sort out the contacts through the API but you could sort them out with their id or date_applied values.
We have to sort the Tagged Contacts by the date_applied parameter.
Then also the listing of Tagged contact is in ascending order. But if there are more than 1000 tagged contact the contacts after 1000 are not been displayed as new contacts are added to the bottom.
Is there any possible way to fix this?
I think you will have to do the workaround with a function, you can do a while loop changing the offset to 1000, 2000 and so on until you get all your contacts, you will know if there are more requests needed using the next parameter on the callback, then you will add then to a mapped list and sort say list with the date attribute either descending or ascending.
We are always improving the ability of our APIs to provide access to your Keap data, and I will pass the request along to our product manager for future implementation.