Merchant listings Product Structure Data Missing shippingDetails and hasMerchantReturnPolicy

Reproduce: Add product structure data and include product offer schema - test the schema on rich result test warning will show with merchant listing , example: https://xglobal-tents.com

summary-proposed-resolution:
-1 https://schema.org/MerchantReturnPolicy

-2 https://schema.org/OfferShippingDetails

example of complete code solution:

<script type="application/ld+json" class="saswp-schema-markup-output">
[{"@context":"https:\/\/schema.org\/","@graph":[{"@context":"https:\/\/schema.org\/","@type":"SiteNavigationElement","@id":"https:\/\/barm.se#Top Menu","name":"Nagelt\u00e5ng","url":"https:\/\/barm.se\/produkt-kategori\/nageltang\/"},{"@context":"https:\/\/schema.org\/","@type":"SiteNavigationElement","@id":"https:\/\/barm.se#Top Menu","name":"Nagelbandst\u00e5ng","url":"https:\/\/barm.se\/produkt-kategori\/nagelbandstang\/"},{"@context":"https:\/\/schema.org\/","@type":"SiteNavigationElement","@id":"https:\/\/barm.se#Top Menu","name":"Blogg","url":"https:\/\/barm.se\/blogg\/"},{"@context":"https:\/\/schema.org\/","@type":"SiteNavigationElement","@id":"https:\/\/barm.se#Top Menu","name":"Kontakt","url":"https:\/\/barm.se\/kontakt\/"},{"@context":"https:\/\/schema.org\/","@type":"SiteNavigationElement","@id":"https:\/\/barm.se#Top Menu","name":"L\u00e4gg till salong","url":"\/salonger"}]},

{"@context":"https:\/\/schema.org\/","@type":"Product","@id":"https:\/\/barm.se\/produkt\/nagelklippare-for-tjocka-tanaglar-fargad\/#Product","url":"https:\/\/barm.se\/produkt\/nagelklippare-for-tjocka-tanaglar-fargad\/","name":"Nagelklippare f\u00f6r tjocka t\u00e5naglar - 14cm f\u00e4rgad","sku":"NTTLK-2035","description":"Har du h\u00e5rda naglar som \u00e4r sv\u00e5ra att klippa? D\u00e5 \u00e4r en titaniumf\u00e4rgad nagelklippare f\u00f6r h\u00e5rda naglar ett bra alternativ. Den \u00e4r tillverkad i rostfritt st\u00e5l och har en handslipad egg som g\u00f6r att den enkelt och s\u00e4kert kan sk\u00e4ra igenom \u00e4ven de h\u00e5rdaste naglarna.","offers":{"@type":"Offer","availability":"https:\/\/schema.org\/InStock","price":"199","priceCurrency":"SEK","url":"https:\/\/barm.se\/produkt\/nagelklippare-for-tjocka-tanaglar-fargad\/","priceValidUntil":"2025-12-26T20:30:57+00:00","hasMerchantReturnPolicy":{"@type":"MerchantReturnPolicy","applicableCountry":"SE","returnPolicyCategory":"MerchantReturnFiniteReturnWindow","merchantReturnDays":"14","returnMethod":"ReturnByMail","returnFees":"FreeReturn"},"shippingDetails":{"@type":"OfferShippingDetails","shippingRate":{"@type":"MonetaryAmount","value":"0","currency":"SEK"},"shippingDestination":{"@type":"DefinedRegion","addressCountry":"SE"},"deliveryTime":{"@type":"ShippingDeliveryTime","handlingTime":{"@type":"QuantitativeValue","minValue":"0","maxValue":"1","unitCode":"DAY"},"transitTime":{"@type":"QuantitativeValue","minValue":"2","maxValue":"3","unitCode":"DAY"}}}},"mpn":"665","brand":{"@type":"Brand","name":"BARM - klipp tjocka t\u00e5naglar"},"aggregateRating":{"@type":"AggregateRating","ratingValue":"5","reviewCount":1},"review":[{"@type":"Review","author":{"@type":"Person","name":"Abbe"},"datePublished":"2024-01-23T17:06:17+01:00","description":"Har du h\u00e5rda naglar som \u00e4r sv\u00e5ra att klippa? D\u00e5 \u00e4r en titaniumf\u00e4rgad nagelklippare f\u00f6r h\u00e5rda naglar ett bra alternativ. Den \u00e4r tillverkad i rostfritt st\u00e5l och har en handslipad egg som g\u00f6r att den enkelt och s\u00e4kert kan sk\u00e4ra igenom \u00e4ven de h\u00e5rdaste naglarna.","reviewRating":{"@type":"Rating","bestRating":"5","ratingValue":"5","worstRating":"1"}}],"image":[{"@type":"ImageObject","@id":"https:\/\/barm.se\/produkt\/nagelklippare-for-tjocka-tanaglar-fargad\/#primaryimage","url":"https:\/\/barm.se\/wp-content\/uploads\/2024\/01\/Nageltang-for-harda-naglar-Titanium-14cm-NTTLK-2035-01-1-1200x798.jpg","width":"1200","height":"798","caption":"Nagelt\u00e5ng titanium"},{"@type":"ImageObject","url":"https:\/\/barm.se\/wp-content\/uploads\/2024\/01\/Nageltang-for-harda-naglar-Titanium-14cm-NTTLK-2035-01-1-1200x900.jpg","width":"1200","height":"900","caption":"Nagelt\u00e5ng titanium"},{"@type":"ImageObject","url":"https:\/\/barm.se\/wp-content\/uploads\/2024\/01\/Nageltang-for-harda-naglar-Titanium-14cm-NTTLK-2035-01-1-1200x675.jpg","width":"1200","height":"675","caption":"Nagelt\u00e5ng titanium"},{"@type":"ImageObject","url":"https:\/\/barm.se\/wp-content\/uploads\/2024\/01\/Nageltang-for-harda-naglar-Titanium-14cm-NTTLK-2035-01-1-798x798.jpg","width":"798","height":"798","caption":"Nagelt\u00e5ng titanium"}]}]
</script>