Talaaq has many conditions to be valid. Among the conditions are that
the husband should not be in the state of anger. So the Talaaq which
you mentioned in the state of anger is invalid.
There is another condition in every Talaaq which is that of two pious witnesses hearing
the declaration of Talaaq. Without this condition, no Talaaq is valid.
So the person who was speaking to his wife on phone and told her the
word of ‘Talaaq’, between him and her the Talaaq is invalid because no
two pious men witnessed it.
This person and his wife are still married.