Permission Error when Sharing a List Item returned using Search field

[SueB_Huon]

Within a SharePoint online list (classic) , I can:

• scroll through the list, right click on a list item and share with a user, with type ‘People with existing access can use the link’.
• filter a column to reduce the list to one item and can share with a user, with type ‘People with existing access can use the link’

If I use the Search field (top left corner of screen) and search and reduce the list to one item then Sharing with type ‘People with existing access can use the link’, gives an error of 'Some of the recipients you entered don't have permissions to access the item'. 

Can anyone shed any light on why I can’t share a list item that has been returned using the Search field?  Thanks

[#2]

My guess is because it’s keying off search index results personalized to yourself so they technically wouldn’t have access to your search results. If you chose a different sharing option is it allowed?

[#3]

@Chris Webb Thanks for your reply.  No, changing the sharing type still gives the same error.  We can use Copy Link OK.