Creating ARM instances not possible

When trying to create an ARM instance i get following error

ERROR: Error creating machine: Error in driver during machine creation: could not create server: missing image

When using x86 based images everything works fine

To reproduce try creating a server using either cli or in my case autoscaling Gitlab Runnners

"hetzner-api-token=************", 
"hetzner-image=ubuntu-24.04", 
"hetzner-server-type=cax21", 
"hetzner-server-location=nbg1"

Leads to ERROR: Error creating machine: Error in driver during machine creation: could not create server: missing image

"hetzner-server-type=cx22" This works

I also tried specifying the image id from the API e.g. 161547270 (Ubuntu 24.04 on arm) which leads to this error

ERROR: Error creating machine: Error in driver during machine creation: could not create server: image has incompatible architecture (invalid_input)

For context: Im running an autoscaling server for Gitlab runners. The "broker" (The server that autoscales the other servers) runs on x86

Start by reproducing the failure through the CLI or the autoscaling GitLab Runner path with an Ubuntu 24.04 image, comparing the cax21 ARM server type with the working cx22 type. Check how the driver selects and validates images for each architecture, including the reported image ID. Done means ARM instance creation succeeds while x86 behavior remains unchanged.