In fact, Coya AG will be part of the Luko group once the BaFin approves the transaction. After the BaFin approoval, only the name will change. Your contract is still delivered by Coya AG which is a registered single stock company (AG) in Germany. It will always remain as the underlying insurance company providing your insurance.
You will be covered by the same guaranties, in the same conditions. Only a few practical things will change :
Your payment date : it will now be on the 8th of the month. You should have received an email to inform you about this change.
You will communicate with Luko rather than with Coya for contract and claims matters
You may wonder, if Luko offer more services I don't need, will I have the opportunity to refuse them ?
Luko services will remain exactly the same you got at Coya. So no worries about that.