IKEA trådfri disappears from HomeKit when paired with HP23

Hey,
I am in the process of moving my Ikea devices to Homey pro 2023 and when I moves my fyrtur curtain it disappeared from HomeKit (it is not responsive from the HomeKit app).

Anyone know what I can do to make it work again?

Of course, because you deleted the linked Fyrtur curtain from your old Homey, so it will be deleted also in Apple Home(Kit). The old Homey is a separate bridge in Apple Home(Kit), the new Homey will be a new bridge in Apple Home(Kit). Both Homeys/bridges are independent of each other.
So you have to pair your new HP23 also with Apple Home(Kit) and then the Fyrtur curtain will be available again (via the HP23 bridge).

But I didn’t have an old homey.
I only had homekit and the IKEA trådfri gateway

The issue is the same though: if you remove a device from the gateway, the gateway cannot provide access to it anymore via HomeKit.