use sender UMA only

umad-06-payreq-response.md

@@ -18,8 +18,7 @@ The full structure of the LNURLP response is:
     // A url which the sending VASP should call on transaction completion to notify the receiving VASP of
     // the utxos used to complete the transaction. See [UMAD-07](/umad-07-post-tx-hooks.md).
     "utxoCallback": string,
-    // The receiving VASP's signature over sha256_hash(<sender UMA> (eg. [email protected]) + <receiver UMA> (eg. [email protected]) +
-    // signatureNonce + signatureTimestamp)
+    // The receiving VASP's signature over sha256_hash(<sender UMA> (eg. [email protected]) + signatureNonce + signatureTimestamp).
     "signature": string,
     "signatureNonce": string,
     "signatureTimestamp": number, // in seconds since epoch