Hi KamSauKau,
We'd like to provide some information and suggestions that may help with this issue.
Please go through the following suggestions, which may help:
1. First, please ensure all devices are updated, so we can rule out an issue there. Here’s how to check for an update on Mac: Update macOS on Mac Here’s how to check for an update on iPhone: Update your iPhone or iPad
2. Please check if a firewall is enabled on your Mac, as that can block connections: Block connections to your Mac with a firewall
3. Please confirm that each device has Wi-Fi and Bluetooth enabled, as outlined in the requirements for AirDrop, which are listed here: Use AirDrop on your Mac
4. Please restart each device and test to determine if the issue is still occurring, by using the processes outlined in these links: Restart your iPhone and Shut down or restart your Mac and Restart your iPhone
If the issue continues, please contact Apple Support for assistance. You may be able to reach them here: Contact Apple Support
Thanks!