I had to look up what this was as I'd forgotten but anyway. I used the Atlas to travel to Vinland from Francia and as soon as I arrived I had a pop-up on the screen that I'd acquired "Mysterious Horned Tablet". This is one of the Excalibur things. I presume it's a bug because I have Excalibur. Also I've visited Vinland a few times since getting that sword but it's only just occurred so it's been introduced at some point. I suspect it's since 1.4 something but don't know for certain.
Hey there @spirantcrayon22 , thanks for reporting this. I understand the game gave you another Mysterious Horned Tablet, despite that you were already done with the Excalibur stuff - sorry about that!
Do you still have the tablet now? If so, can you take a screenshot of it for me from your inventory, and another screenshot showing that you've already got Excalibur? Here's our screenshots guide, and the resulting images can be added to a response here in the forum thread using the little image icon above the post edit box.
Thanks @TheNorfolkian and @bielik01 for these additional questions and insights, that's really helped me out 
No worries @spirantcrayon22, thanks
@spirantcrayon22 Gotcha, thanks for confirming that. Does it show up in your inventory when you go to Francia?
No worries @spirantcrayon22!
Just keep us updated if/when you remember!
@spirantcrayon22 Thanks for the update! Just to clarify, the tablet is no longer showing up in your inventory at all? Also, are you still having an issue where you received the extra four Order medallions?
Hey @SpirantCrayon22!
Thank you for updating us and I'm glad to hear you've got the tablet right now. Please let me know if it disappears from your inventory again and I'll be happy to look into it further with you. 
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