A new cat flap can look like an obvious doorway to a person and an unfamiliar moving object to a cat. Expecting the cat to use it immediately may create frustration on both sides. Treat it as something to learn, not a test the cat has failed.
First decide whether the access arrangement is safe and appropriate for your cat and home. A flap leading to a secure enclosure is different from unrestricted outdoor access. Discuss concerns with your veterinarian or an appropriate behaviour professional, especially for a cat with health or mobility needs.
Cats Protection’s outdoor-environment guidance discusses cat-flap access and the surrounding environment. Consider the whole arrangement, including safe return, rather than the opening alone.
Make the equipment familiar
Follow the manufacturer’s installation and introduction guidance. Check that the opening, height and mechanism suit the cat. A noisy latch, awkward step or unstable surface can make the approach difficult before the moving flap is even involved.
Allow the cat to investigate without being pushed through. Use a calm, secure setting and an approach appropriate to the individual. Do not trap the cat outside or remove its normal access in an attempt to force learning.
Separate learning from access control
If the flap uses a microchip or other identification system, confirm the setup through the manual. Test the intended permissions safely and keep a way to intervene. A programmed device should not be assumed to work correctly simply because the indicator light is on.
Keep another reliable route available while the cat is learning. Watch whether the cat approaches comfortably, hesitates at the mechanism or avoids the whole area. Those observations can help you identify a practical obstacle rather than labelling the animal stubborn.
Check the flap regularly for damage, obstruction and battery warnings where relevant. A cat that previously used it may stop because something has changed. The useful outcome is predictable, safe access that the cat can use comfortably, with no need to turn an unfamiliar doorway into a confrontation.