He intended to do tamattu’ and he did ‘Umrah, but then he left and did not do Hajj

If you had done the Hajj of Islam (obligatory Hajj) before, then you do not have to do anything. If you had not done Hajj before, then you should have stayed until you had done the obligatory Hajj. You should hasten to do Hajj as soon as you can.

Shaykh Ibn ‘Uthaymeen said:

If the person who is doing tamattu’ enters ihraam then he decides before he enters ihraam for Hajj not to do Hajj, then he does not have to do anything, unless he had made a vow. If he made a vow to do Hajj this year then he has to fulfil his vow, but if he did not make a vow then there is no blame on him if he does not do Hajj after doing Umrah.