Magento 2.x using Multiple Shipping Address to ship products in customer’s multiple address.
The Following below admin setting required to enable Multiple Shipping Address.
Step [1] – Go STORES > Configuration, redirects Configuration section.
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Step [2] – Left panel, choose SALES > Shipping Settings.
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Step [3] – Right panel, Expand the Origin section
There are following below two part
[a] – Allow Shipping to Multiple Addresses
To Enable select Yes, after uncheck use system value
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[b] – Maximum Qty Allowed for Shipping to Multiple Addresses
Enter required quantity as per Store need.
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Step [4] – Click on Save Config button & run CLI command Flush
Finally, Multiple Shipping setting has been done.