Variation not working after update

The attributes are being sanitized. See https://www.ads-software.com/support/topic/24-common-issue-variations-missing-on-product-pages?replies=1

I rename the file ” mytheme/woocommerce/single-product/add-to-cart/variable.php” add to cart button disappear

https://www.trendyshoponline.com/%E0%B8%AA%E0%B8%B4%E0%B8%99%E0%B8%84%E0%B9%89%E0%B8%B2/%E0%B9%81%E0%B8%AB%E0%B8%A7%E0%B8%99%E0%B8%9D%E0%B8%B1%E0%B8%87%E0%B9%80%E0%B8%9E%E0%B8%8A%E0%B8%A3%E0%B9%80%E0%B8%94%E0%B8%B5%E0%B9%88%E0%B8%A2%E0%B8%A7-3-%E0%B8%A1%E0%B8%B4%E0%B8%A5%E0%B8%AB/

no variation work
https://www.trendyshoponline.com/%E0%B8%AA%E0%B8%B4%E0%B8%99%E0%B8%84%E0%B9%89%E0%B8%B2/%E0%B8%88%E0%B8%B5%E0%B9%89%E0%B9%80%E0%B8%9E%E0%B8%8A%E0%B8%A3%E0%B8%94%E0%B8%B2%E0%B8%A7%E0%B8%81%E0%B8%A3%E0%B8%B0%E0%B8%88%E0%B8%B2%E0%B8%A2%E0%B8%AB%E0%B8%B8%E0%B9%89%E0%B8%A1%E0%B8%97%E0%B8%AD/

Try saving it as well? Have you tried the default WP theme?