Login credential in asp.net

Question

HI, I have created "remember me" option in login Page in my application, it is working fine but i want that it should work like gmail. Means - 

currently it is saving and retrieving credentials but if i ll login with different login details, it is replacing first one with second one.

I want both login credentials  (or n number) it should work, if i select first one ,first password should come same for another also.