This problem because your theme changed some line code of Shopify so please add one line with step by step:
Login admin page of your shopify
Open menu “Online store” and click “Edit code”, see image
Find file “product-template.liquid”, please check image.
Move to end of file and add this code
<script>var inkgo_shopify_gallary_theme_custom = '.product__photos';</script>
Save and check again with your site.