Cognizant Technology Solutions — Not able to modify the pan self declaration in pre join formalities

I received my offer letter recently and I was asked to fill the pre-joining documents. I have filled the personal details form where I was asked to give my current address, Now in the pan declaration form they are asking for my permanent address but it was profiled with my current address which I gave in my personal details form. I couldn't modify it.
NB: my current and permanent details are different.
please give me a solution.