What is the ruling if the two witnesses did not hear the woman giving her consent to the marriage?
Question

                I entered Islam, and when I gave my consent to my wali (guardian) to represent me in my marriage contract, that was by telephone, and in front of two witnesses who were men, but they did not hear the conversation. Is this marriage valid? Because my husband and I have had intercourse, believing that the marriage was valid. If it is not, then is it permissible for me to repeat the marriage contract with him?
Praise be to Allah.
	In order for the marriage to be valid, it is stipulated that 
	the marriage contract should be done by the woman’s guardian, and that it 
	should be witnessed by two Muslim male witnesses, because the Prophet 
	(blessings and peace of Allah be upon him) said: “There is no marriage 
	except with a guardian.” Narrated by Abu Dawood (2085), at-Tirmidhi (1101) 
	and Ibn Maajah (1881), from the hadith of Abu Moosa al-Ash‘ari; classed as 
	saheeh by al-Albaani in Saheeh at-Tirmidhi.

	And he (blessings and peace of Allah be upon him) said: 
	“There is no marriage except with a guardian and two witnesses of good 
	character.” Narrated by al-Bayhaqi from the hadith of ‘Imraan and ‘Aa’ishah; 
	classed as saheeh by al-Albaani in Saheeh al-Jaami‘, no. 7557.

	The woman’s guardian is her father, then her father’s father, 
	then her son (if she has one), then her full brother, then her brother 
	through her father, then  the son of her full brother, then the son of her 
	brother through her father, then her paternal uncle, then his son, then the 
	Muslim ruler.

	Al-Mughni 
	(9/355)

	If the woman is a Muslim, it is stipulated that her guardians 
	should also be Muslim.

	Ibn Qudaamah (may Allah have mercy on him) said:

	With regard to a disbeliever, he has no guardianship over a 
	Muslim woman under any circumstances, according to the consensus of the 
	scholars, including Maalik, ash-Shaafa‘i, Abu ‘Ubayd and as-haab ar-ra’y. 
	Ibn al-Mundhir said: Those scholars from whom we acquired knowledge 
	unanimously agreed on this point.

	End quote from al-Mughni (9/377)

	Based on that, if your guardian is a Muslim, then the 
	condition of having a guardian was fulfilled.

	But if he was not Muslim, then the marriage contract is not 
	valid, and must be repeated at the hands of your Muslim guardian, if you 
	have one. If you do not have one, then the Muslim judge must do your 
	marriage contract, if there is a Muslim judge; otherwise it may be done by 
	the director of the Islamic centre or someone of similar standing among the 
	Muslims. If no such person is available, then a Muslim man of good character 
	may do your marriage contract.

	With regard to witnesses, what is meant is that the marriage 
	contract must be witnessed by two Muslim witnesses who are present at the 
	marriage contract that is done between the guardian and the suitor. Everyone 
	who is present at the marriage contract, such as a scribe, relative, 
	official and so on is a witness to it, if he is fit to be a witness, i.e., 
	he is a Muslim of good character.

	Many of the scholars are of the view that if the marriage is 
	publicised widely and announced, there is no need for there to be witnesses, 
	because of the report narrated by Ahmad from ‘Abdullah ibn az-Zubayr (may 
	Allah be pleased with him), according to which the Prophet (blessings and 
	peace of Allah be upon him) said: “Publicise the marriage.” This hadith was 
	classed as hasan by al-Albaani in Irwa’ al-Ghaleel no. 1993.

	Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) 
	said: Undoubtedly marriage that is publicised widely is valid, even if it is 
	not witnessed by two witnesses. But if it is done in secret and with 
	witnesses, this is something that is subject to further discussion.

	If it is both witnessed and widely publicised, then there is 
	no dispute that it is valid.

	If there are no witnesses and it is not widely publicised, 
	then it is invalid according to the majority of scholars, and if there is 
	any differing opinion it is insignificant.

	End quote from al-Ikhtiyaaraat al-Fiqhiyyah, p. 177

	See also the answers to questions no. 
	124678 and 112112

	Based on that, if these two witnesses witnessed the marriage 
	contract, or the marriage was widely publicised and announced, then your 
	marriage is valid; if that was not the case, then you must do a new marriage 
	contract.

	And Allah knows best.