A man from the Companions of the Prophet ﷺ came to Umar ibn al-Khattab (may Allah be pleased with him). He bore witness before him that when he (the Prophet) was suffering from a disease of which he died he heard the Messenger of Allah ﷺ prohibiting performing of umrah before hajj. (Using translation from Abū Dāʾūd 1793)
أَنَّ رَجُلًا مِنْ أَصْحَابِ رَسُولِ اللهِ ﷺ أَتَى عُمَرَ بْنَ الْخَطَّابِ ؓ فَشَهِدَ عِنْدَهُ أَنَّهُ سَمِعَ رَسُولَ اللهِ ﷺ فِي مَرَضِهِ الَّذِي قُبِضَ فِيهِ يَنْهَى عَنِ الْعُمْرَةِ قَبْلَ الْحَجِّ