Have one contact that i can't facetime on my ipad air 2 but works correctly on my iphone 5s

Hi,

I have one contact with whom i can't facetime on my ipad air 2 it shows the error that the contact is not available for facetime.

But for the same contact i can facetime on my iphone 5s with out any trouble.

I have checked the contact number and email address is same as on my iphone 5s and ipad air 2.

I tried to delete and add back the contact on my ipad air 2 but to no vail.

I even formatted my ipad air 2, but still to no avail.

Please note my id is same for ipad air 2 and iphone 5s.

If that contact facetimes me, i can receive the facetime on both ipad air 2 and iphone 5s.

Problem occurs, when i try to facetime that particular contact from my ipad air 2.

And there is no problem with other contacts.

Please advise.

Thanks

Rahul.