Answer
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
1- The decision to hold a limited Hajj due to Coronavirus (COVID-19) pandemic is something beyond your power and you have no choice in it.
2- You are released from the burden of the vow you made to make hajj.
3- In the future, do not burden yourself with a vow for Hajj. You can just go as an act of worship whenever you can.
Answering your question, Sheikh Kifah Mustapha, the Imam and Director of The Prayer Center of Orland Park and representative for Dar El Fatwa of Lebanon in the US, states:
What’s a Vow?
Making an oath in the form of vow (nadhr) is permissible in Islam. Allah the Almighty spoke about Mary the mother of Jesus saying: {…and if you see any human being, say: ‘Verily! I have vowed a fast unto the Most Beneficent (Allah) so I shall not speak to any human being this day} (Maryam 19:26)
A vow means to obligate a matter on yourself that God did not ordain on you.
If someone made a vow, he must act on the oath he made as it becomes an obligation. Allah said: {They [are those who] fulfill [their] vows and fear a Day whose evil will be widespread.} (Al-Insan 76:7)
Now, Hajj is an obligating that needs no vow to be performed. Allah said: {And [due] to Allah from the people is a pilgrimage to the House – for whoever is able to find thereto a way. But whoever disbelieves – then indeed, Allah is free from need of the worlds.} (Aal Imran 3:97)
But people can make a vow for the timing of the Hajj trip, which I can understand is the case in your question here.
Making a Vow to Make Hajj
If you had made the intention and took steps for trip reservations and was ready to travel for Hajj but circumstances came that prevented you from going against your ability, then you are released from this vow.
Allah said: {Allah does not charge a soul except [with that within] its capacity.} (Al-Baqarah 2:286)
The Prophet Muhammad (peace be upon him) said: “Allah will not hold burden over my Ummah on matters that is of forgetfulness, mistakes or that which was forced on them.” (Ibn Majah)
The decision to hold a limited Hajj for the year 2020 because of the Coronavirus (COVID-19) pandemic is something beyond your power and you have no choice in it.
The ruling is that you are released from the burden of the vow you made to offer hajj.
For next year or the years after, I suggest that you do not burden yourself with a vow for Hajj. You can just go as an act of worship of one of the five pillars of Islam whenever you can.
Almighty Allah knows best.