How to change password hint on registration page

The LearnPress registartion page says “The password should be at least 12 characters long” where as it accepts passwords of length 6 characters. How can we change this hint in basic Learnpress theme.

I tried doing changes in desc of function get_register_fields() in class-lp-register-form.php however its not reflecting on my site. Is there any cache refresh is required after doing any change. Please share the steps.

Thanks in advance.