It is here ASP.NET Identity reset password
UserManager<IdentityUser> userManager =
new UserManager<IdentityUser>(new UserStore<IdentityUser>());
userManager.RemovePassword(userId);
userManager.AddPassword(userId, newPassword);
It is here ASP.NET Identity reset password
UserManager<IdentityUser> userManager =
new UserManager<IdentityUser>(new UserStore<IdentityUser>());
userManager.RemovePassword(userId);
userManager.AddPassword(userId, newPassword);