Remove the prefix if it is a category archive or post type archive.

memberlite_remove_prefix_from_the_archive_title.php

<?php
/**
 * Remove the prefix if it is a category archive or post type archive.
 * 
 * You can add this recipe to your site by creating a custom plugin,
 * adding the customization to a Memberlite child theme,
 * or using the Code Snippets plugin available for free in the WordPress repository.
 * Read this companion article for step-by-step directions on either method.
 * https://memberlitetheme.com/create-a-plugin-for-customizations-to-your-memberlite-site/
 */ 
function memberlite_remove_prefix_from_the_archive_title( $prefix ) {
	// Add any other post type archives or taxonomy labels to this array.
	if ( in_array( $prefix, array( 'Archives:', 'Category:' ) ) ) {
		$prefix = '';
	}
	return $prefix;
}
add_filter( 'get_the_archive_title_prefix', 'memberlite_remove_prefix_from_the_archive_title' );