How to reset string's input?

I have two strings, sring1 has preset value and string2 value has to be typed in to check if its the same as string1's value.

When I type in the correct value for string2 and door unlocks, value(numbers typed in) stay on screen.

What code do I need to reset string2's inputted value to none, so it don't show on screen?

for reset the string:

for hide the text from screen, reset the SHOW-flag of this text.

Thank you so much.

I was looking at the str_cpy in the code that I was working on but I just couldn't put 2 and 2 together and use it.
LOL, I suck at this.

Thank you again.