You probably have the v3 of the strip (with Bluetooth support), which is only in the SDKv3 (test channel) app (Homey v5 only).
The lightstrip plus in the stable app only has the non Bluetooth version (a.k.a. v2)
As there is already an sdkv3 app in the store the developer can’t add devices into the stable app anymore, so you either need to update to the experimental update and hope everything works for you (and don’t have any other zigbee apps that haven’t been rewritten to sdkv3 (which is mandatory)), or wait until Homey v5 is in stable.
