Problem with ACF and searching by text

Hi,

I have problem with using this plugin with ACF Gallery. When I am searching product its attribute everything is ok, gallery of colors under text is displayed:

colors displayed

Problem appears when I try to search by text, I wrote the name of the product:
problem

Colors under text are not displaying, I am getting:
Illegal string offset ‘url’ in woocommerce/content-product.php

My code there is:

$images = get_field('colors');

if( $images ) { ?>
        <?php 
		for ($i = 0;$i < count($images) && $i < 38;$i++) { ?>
        
		<img src="<?php echo $images[$i]['sizes']['thumbnail']; ?>" alt="<?php echo $images[$i]['alt']?>" />         
   <?php } ?>  
<?php } ?>

I know it may be caused directly by ACF, but I want to ask here too.