Not tracking all Purchase

Hello, I have worked with many woocommerce stores and never faced this problem, so I have setup the gtm4wp plugin and all tags on tag manager as recommended, but in this case, it is not tracking the sales happening on the website. only 10% of sales count on google analytics report and we have been monitoring it for nearly one month, can you please help me. For Now I have removed the gtm4wp plugin.

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