How to check transaction data received in Liqpay server_url?

Question

PHP

Good afternoon
Thank you for paying attention to my question.
There is a store and liqpay connected to it. Tried both with the SDK and on my own. Payment with sandbox=1 option. Scheme of work:

1. Forming an array with payment data
   
2. do Data and Signature
   
3. I submit the form
   
4. I go through the whole procedure in liqpay
   
5. I accept in server_url formed by the Data and Signature service
   

Question! What to compare for transaction validation? Sent Data and Signature and received Data and Signature do not match!
I know about checking the status through the API ... This option is not considered. Interested in checking the payment before moving to the result_url. Is it possible to validate a transaction without a request to the payment/status API?
Thanks

Answer 1

All found! Thank you!

Answer 2

Data that comes in response to server_url encoded in base64. You just need to decode.