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1 - Check your Filters to make sure your List View is filtered by 1 Record Type. See https://ceceuofu.atlassian.net/wiki/spaces/~elizabeth.aste/pages/2479259649/Salesforce+-+List+Views+Overview#4---See-List-View-Filters
You will not be able to edit records inline if the List View is not filtered by 1 Record Type.
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