She did tawaf for ‘umrah, then she went to Madinah, and did sa`i after she returned
Question

A woman entered ihram with the intention of doing ‘umrah. She circumambulated the Ka‘bah (tawaf) and prayed behind Maqaam Ibraaheem, then she went with her group to visit al-Madinah al-Munawwarah, and came back on the same day and did sa`i. Is her ‘umrah valid, or does she have to do something?
Praise be to Allah.It is not stipulated that sa`i should be done straight after tawaf, according to the view of the majority of fuqaha’. So if someone does tawaf then delays sa`i for a day or more, his sa`i is valid.
Ibn Qudaamah (may Allah have mercy on him) said in al-Mughni (10/240): It is not essential that sa`i should be done straight after tawaf.
Imam Ahmad said: There is nothing wrong with delaying sa`i in order to rest, or until afternoon.
‘Ata’ and al-Hasan did not see anything wrong with someone circumambulating the Ka‘bah at the beginning of the day and delaying [sa`i between] as-Safa and al-Marwah until afternoon. Al-Qaasim and Sa‘eed ibn Jubayr did that. End quote.
See: al-Majmoo‘ (8/99); al-Mawsoo‘ah al-Fiqhiyyah (25/18); and the answer to question no. 109320 .
Based on that, this woman’s ‘umrah is valid, and it does not matter that she went to Madinah between tawaf and sa`i.
And Allah knows best.