CANNOT ADD ZOHO CONTACTS TO MOBILE ACCOUNT

CANNOT ADD ZOHO CONTACTS TO MOBILE ACCOUNT

GOOD EVENING ,
  IN MY PHONE I CAN ADD MY GMAIL CONTACTS 
                                               SIM CONTACTS 
                                               PHONE CONTACTS ETC 
SO THAT I COULD SEE WHO IS USING SOCIAL MEDIAS SUCH AS WHATS APP,  WE CHAT,  IMO  , ETC AND I COULD SEND MESSAGES TO THEM 

BUT I CANT ADD MY ZOHO CONTACTS TO MY MOBILE CONTACTS( THERE IS AN OPTION IN PHONE SETTINGS AS ADD ACCOUNTS AND I HAVE ADDED MY ZOHO MAIL TO MY PHONE CONTACT BUT I CANT SEE ANY CONTACTS IN PHONE ) SO THAT I CANNOT SEE ANY BODY IS USING SOCIAL MEDIAS  SO THAT I CANT SEND MESSAGES TO THE CONTACTS IN MY ZOHO CONTACTS 

PLEASE HELP ME