First, make sure that all of your devices are logged into the same LINE account.
Open LINE on your main device, go to the Home tab, then Settings, then Stickers, then My Stickers, and tap "Download all" to get your sticker sets back.
It's important to remember that some things, like Coins, can't be moved from one operating system to another.
Find your purchase history in the LINE app by going to Settings > Stickers > Purchase History. If the stickers still don't show up, check that you bought them.
If the stickers are shown there but not on your device, delete them and then download them again.
Remove the bad set by going to Settings > Stickers > Sticker Set Order. Then, go back to My Stickers and download it again.
Do you have another way to solve it? We'd love to hear from you in the comments.
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