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First off, we need to add some fields to the page layout for Product. Subscription25 comes with a default Product layout which has these fields included and which you can assign to profiles.
Navigate to the Object Manager in Setup
Navigate to the Product object
Click the Page Layouts tab
Click the Page Layout Assignment button
Reassign the Subscription25 page layout to the correct profiles, if this layout is not available you have to perform the following actions.
Add the manage administration button to the button section
Add The Cost Type field to the layout.
Add the Administration Products related list to the related list section.
There should now be a button on a product called “Manage administrations”
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