Are you working with wordpress shortcode and failure to use it in widget by text area. to make if working 1st make sure your created Shortcode ok as per it structure syntax and once try them to test by adding in Page post content.
if Shortcode working ok that mean no issue with your created shortcode. now check for below filter as it was added in your active themes functions.php or any included file.
add_filter( 'widget_text', 'do_shortcode', 7);
if not below widget_text filter than you go solution for Shortcode not working with text area widget. just add above syntax in active theme folder functions.php
i believe now your created Shortcode working well with Text Area Widget in Wordpress