Hay Day duplicated my farm on another device, how can I merge them correctly?

Hay Day's creator, Supercell, only lets you connect one farm to a Supercell ID at a time, so you can't combine two farms into one.

The official Supercell support page says that you can use your Supercell ID to switch between different accounts, but not to merge them.

One farm can be linked to your Supercell ID, and then you can stop using the other farm.

Go to each farm's Settings page, then Supercell ID, and finally Link or Log Out. Then, on your new device, use your Supercell ID to sign in with the farm you want to play on.

Contact Supercell Support in-game through Help & Support if you think the copy showed up because of a mistake, like sync a new device before properly linking it.

Tell them about both farms (name, level, and device) and ask them to recover the right one. Remember to include your Supercell ID email and, if you have them, any records for purchases.

If the problem remains unresolved, consider filing a complaint on Xolvie to raise awareness about the issue and inform others.