1. You can try to communicate with the developer first to understand the reasons for overdue delivery and negotiate possible solutions.
2. If the communication fails, you can complain to the local real estate authorities and ask them to supervise the developers to urge them to hand over the house as soon as possible.
You can also consider bringing a lawsuit to the court, demanding the termination of the contract and claiming damages. If your contract contains a default clause of delayed delivery, you can claim compensation according to the terms of the contract.
It should be noted that the specific implementation of the above measures depends on the specific situation. It is recommended that you consult a professional lawyer or relevant institutions for more detailed and accurate information and suggestions.