How do I get my contact list to add in Whatsapp?

[AC Question]

Not getting contact list to add in watsapps

i am having Samsung S3 mini . in my contact list watsapp icon are showed on all contacts but when i go to watsapps and click to add contact icon it shows no watsapps contact in list.i am unable to add contact in watsapps and those who are already added those contact name are not been mentioned only contact number are showed in watsapp.