Abu Dharr used to say about a person who makes the intention of Hajj but he repeal it for the ‘Umrah (that will not be valid). This cancellation of hajj for ‘Umrah was specially meant for the people who accompanied the Messenger of Allah ﷺ.
Related hadith on this topic
Explanation & Benefits
Shaykh Umar Farooq Saeedi
1807. Commentary: This was the opinion of Abu Dharr, otherwise there is no harm if a person initially enters the state of ihram with the intention of Hajj and then changes it to ‘Umrah. A large number of the Companions (radi Allahu anhum) hold this view.
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 1807