Recovery takes time
A newly moulted tarantula has a soft exoskeleton and soft fangs. It may not be ready to hunt even after it begins moving around normally.
Look at the fangs
Dark, hardened fangs are a useful visual sign that recovery has progressed. Larger spiders usually need more time than tiny slings.
Do not rush feeding
Offering prey too early creates unnecessary risk. A healthy tarantula has enough reserves to wait until the mouthparts and body are ready.
Water
Keep water available. Drinking after a moult is normal and useful while the animal restores fluids.
If refusal continues
A spider may still decline the first meal after recovery. Remove the prey and try later rather than repeatedly disturbing the enclosure.
When refusal is abnormal
Concern increases if the spider cannot move normally, has damaged mouthparts, shows a severe failed moult or loses condition steadily. Ordinary post-moult fasting is common.