Recent Posts Widget not displaying most recent posts right away

Sometimes the most recent posts display right away on the main page of the web site where the Recent Posts are supposed to be displayed. However, other times … like right now … the most recent posts do not display in this section of the web site until the next day. Would like to know why this is the case and, if possible, how to fix this issue, so that the most recent posts always display right away. Thank you.

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