Generate a hashed message with SHA256 hmac in php (key & msg are fake)

I’m using php 8.0.11, i have to generate a SHA256 encrypted messagesignature.When i test the API in postman with javascipt code in Pre-request script it give the right encrypted messagesignature, i converted the script to php when i test it in php it sends a different wrong encrypted messagesignature (key & msg are fake) :