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Hi @Tlfryer - there could be a conflict with two devices, though it is possible if they don't both use the gallery for watch faces, IE an inspire and a Sense, or for children's watches.
What you can do is have 2 accounts and simply login to the account with the watch you are using.
You need to sync about at least every 5 days and you can use the SimpleCheckUp app to tell you on the watch when you last synced.
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