Breaking a banner in Bedrock versions (Win 10, Android, iOS) will cause a ghost item to appear instead. Breaking by hand the item breaks properly. If you place the ghost item on the wall you can no longer remove it. You can not alter the banner in any way. Assumtion you are unable to clone it but have not tried. You can only destroy it with fire.
MCPE-27945
Breaking banner with Silk created glitched ghost item
Resolved
Duplicate
1
Thank you for your report!
However, this issue has been has been reported already in a private ticket.
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