List index too large how to solve

Could anyone help with it? Thanks!
This the the forgot pw page.

You do not show how you set / what contains global listUserInformation

So sorry for missing it

your list is empty can u show the data returned from cloud db

this is the blocks on the register screen

check this global variable, what you are getting by debuging this variable.. (click Do it on right clicking the mouse after connecting with companion)