ANSWER:

You must look at all the bank statements of these past years and must pay zakat for all these years if the savings reached or was above nisab and you must repent sincerely to Allah as zakat is one of the pillars of Islam and you cannot be so easy about not fulfilling this obligation.

I’ve been working as a freelancer since 2011 neither I know to pay zakat on money nor I remember how much money I had by end of every past year but after 2017 I have money in bank by end of year and I decided in 2018 to pay zakat on my money in 2019 around august.so as far i do not remember the past years in which i dont remember my money what should I do for years before 2017.Im afraid now