Ibn ‘Abbas reported the Prophet ﷺ as saying If a man raises his voice in talbiya for Hajj, then he comes to Makkah, goes round the House(the Ka’bah) and runs between Al Safa’ and Al Marwah he may take off his ihram. That will be considered as ihram for ‘Umrah. Abu Dawud said Ibn Juraij narrated from a man on the authority of ‘Ata that the companions of the Prophet ﷺ entered Makkah raising their voices in talbiyah for Hajj alone, but the Prophet ﷺ changed it to ‘Umrah.
عَنِ النَّبِيِّ ﷺ قَالَ إِذَا أَهَلَّ الرَّجُلُ بِالْحَجِّ ثُمَّ قَدِمَ مَكَّةَ فَطَافَ بِالْبَيْتِ وَبِالصَّفَا وَالْمَرْوَةِ فَقَدْ حَلَّ وَهِيَ عُمْرَةٌ