Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 6 months ago

If you are sure that you made a Nadhr, then you must fulfill it in every possible way. If you are not sure that you made a Nadhr, then nothing is obligatory on you.
If you did a Nadhr and you deliberately did not fulfill it, there is a Kaffara on you which is: feeding ten poor believers or clothing them. If you are unable to afford that then fasting three days.

Wassalam.