If your store is in an eligible country but you're not seeing Shopify Payments appear, then Shopify Payments has likely been removed from your store. You can contact Shopify Support to confirm this and to find out if Shopify Payments can be reconsidered for your store. You can contact Shopify Support by logging into your store through the help center, searching your question/issue, then selecting "continue" at the bottom of the page that displays the search results.
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