Creating a shortcode to show vendor biography anywhere on your page

functions.php

<?php
/**
 * Plugin Name: Dokan Vendor Biography Shortcode
 */
add_shortcode( 'dokan_vendor_bio', 'dokan_vendor_bio_shortcode' );
function dokan_vendor_bio_shortcode() {
	$vendor = dokan()->vendor->get( get_query_var( 'author' ) );
	$store_info = $vendor->get_shop_info();
	if ( empty( $store_info['vendor_biography'] ) ) {
		return;
	}
	printf( '%s', apply_filters( 'the_content', $store_info['vendor_biography'] ) );
}


// user vendor bio shortcode on single product page 

add_shortcode( 'dokan_vendor_bio_single', 'dokan_vendor_bio_shortcode_single' );
function dokan_vendor_bio_shortcode_single() {
global $product;
$seller = get_post_field( 'post_author', $product->get_id());
$author = get_user_by( 'id', $seller );
$vendor = dokan()->vendor->get( $seller );

 $store_info = dokan_get_store_info( $author->ID );

 if ( !empty( $store_info['vendor_biography'] ) ) { ?>
     <span class="details">
             <?php printf( $vendor->get_vendor_biography() ); ?>
         </span> 
     <?php
 }
}

think the $store_info array changed a bit. we changed line 8 to $store_info = dokan_get_store_info($vendor->id); you might want to update your code.