diff --git a/lib/2wp-utils.js b/lib/2wp-utils.js
index 70b108e2..03c6be43 100644
--- a/lib/2wp-utils.js
+++ b/lib/2wp-utils.js
@@ -199,7 +199,7 @@ const ensurePeginIsRegistered = async (rskTxHelper, peginBtcTxHash, expectedUtxo
  * @param {RskTransactionHelper} rskTxHelper 
  * @param {BtcTransactionHelper} btcTxHelper 
  * @param {number} amountInBtc 
- * @returns {string} the pegin tx hash
+ * @returns {Promise<string>} the pegin tx hash
  */
 const donateToBridge = async (rskTxHelper, btcTxHelper, donatingBtcAddressInformation, amountInBtc) => {
     const data = [];