Dose mbed OS 5 Support has been finished?

Hello. I was able to use Mbed OS 5 until the other day, but today when I tried to build an Mbed OS 5 project that I created in the past, it failed to build.

These are the code of platform.ini and error.

platform = ststm32
board = nucleo_f303k8
framework = mbed
upload_protocol = stlink
platform_packages = framework-mbed@~5.51203.190509

build_flags = -std=gnu++11
Processing nucleo_f303k8 (platform: ststm32; board: nucleo_f303k8; framework: mbed)
Tool Manager: Installing platformio/framework-mbed @ ~5.51203.190509
UnknownPackageError: Could not find the package with 'platformio/framework-mbed @ ~5.51203.190509' requirements for your system 'darwin_arm64'

I have been using Mbed OS 5 by using platform_packages = framework-mbed@~5.51203.190509, but is this no longer usable?

Is there any way to revive the Mbed OS5 code I wrote in the past?

The only mbed 5 version still present in the registry is 5.15.6 (~6.51506.0). The rest seem to have been deleted from the registry. Whether it’s still supported by Arm, I don’t know.