How do i remember text imputted into a feild

im stuck on something rather easy yet i cant figure it out i need help on when a user inputs some text and if it comes back as an Undefined Error i want it to show what the user typed in so they can see if they misstyped,

Dynamic text feild is called = remember
and the Text Input box is = vrm_ti

CODE:

remember.text = vrm_ti.text;