How Implement an HMAC signature to verify webhooks Issue in Laravel ?

[codeking]

I have implemented HAMC Verification webhook process as given above screenshots. but when I try re-run and get same error again.


Please help me sort-out this problem and let me know where I am wrong? 

Thanks, 

[codeking]

give solution please...?

[codeking]

please list here

[codeking]

how much cost ?