Invalid Signature Incoming webhook

I generated signature in cmd as it was in example:
echo -n “{format}&{timestamp}&{input message}” | openssl dgst -sha256 -hmac {secret} -binary | base64

I used timestamp=30000.
Then I send this request:
curl ‘…integrations.zoom.us/chat/webhooks/incomingwebhook/<…> format=message&timestamp={timestamp}’ -X POST -H ‘Authorization: {authorization}’ -H ‘Content-Type: application/json’ -d ‘Hello World’

I entered the generated signature into the authorization and received the error: Invalid Signature.
Please, help, I need to send message only by secure connection, it’s my task at work. I’m working as an intern and I’m already on the verge of despair(