https://stripe.com/docs/webhooks/signaturesThe signed_payload string is created by concatenating:
The timestamp (as a string)
The character .
The actual JSON payload (i.e., the request body)
Step 3: Determine the expected signature
Compute an HMAC with the SHA256 hash function. Use the endpoint’s signing secret as the key, and use the signed_payload string as the message.
Вот оно и не совпадает, скотина