Vault plugin error: unable to determine plugin type - hashicorp-vault

Question

I am getting this error:
Error writing data to sys/plugins/catalog/example-auth-plugin: Error making API request.
URL: PUT http://127.0.0.1:1234/v1/sys/plugins/catalog/example-auth-plugin
Code: 500. Errors:
* 1 error occurred:
* unable to determine plugin type
After running this command:
# vault write sys/plugins/catalog/example-auth-plugin \
> sha_256="${SHA256}" \
> command="vault-auth-plugin-example"
I am running everything in a container.
podman run \
--rm \
--cap-add=IPC_LOCK \
-p '8200:8200' \
-e 'VAULT_ADDR=127.0.0.1:1234' \
-e 'VAULT_DEV_LISTEN_ADDRESS=127.0.0.1:1234' \
-v './data/:/var/lib/vault' \
-v './code/vault-auth-plugin-example:/etc/vault/plugins/vault-auth-plugin-example' \
-e 'VAULT_LOCAL_CONFIG={"backend": {"file": {"path": "/vault/file"}}, "log_level": "debug", "disable_mlock": true, "listener": [{"tcp": {"tls_disable": true}}], "plugin_directory": "/etc/vault/plugins/", "default_lease_ttl": "168h", "max_lease_ttl": "720h"}' \
--name=dev-pam-vault \
vaultplugin
Vault version: Vault v1.3.0
I did run this command first:
export SHA256=$(shasum -a 256 "/etc/vault/plugins/vault-auth-plugin-example" | cut -d' ' -f1)
I also tried:
# vault write sys/plugins/catalog/example-auth-plugin \
> sha_256="${SHA256}" \
> command="vault-auth-plugin-example"
But then I get this error:
Error writing data to sys/plugin/catalog/example-auth-plugin: Error making API request.
URL: PUT http://127.0.0.1:1234/v1/sys/plugin/catalog/example-auth-plugin
Code: 404. Errors:
* 1 error occurred:
* unsupported path
Any ideas?
Thank you in advance.