diff --git a/src/controllers/wallet/atomic-swap/tx-proposal.controller.js b/src/controllers/wallet/atomic-swap/tx-proposal.controller.js
index 62966315..f87fa228 100644
--- a/src/controllers/wallet/atomic-swap/tx-proposal.controller.js
+++ b/src/controllers/wallet/atomic-swap/tx-proposal.controller.js
@@ -16,11 +16,11 @@ const {
 } = require('@hathor/wallet-lib');
 const atomicSwapService = require('../../../services/atomic-swap.service');
 const { parametersValidation } = require('../../../helpers/validations.helper');
-const { lock, lockTypes } = require('../../../lock');
+const { lockTypes } = require('../../../lock');
 const { mapTxReturn, runSendTransaction } = require('../../../helpers/tx.helper');
 const constants = require('../../../constants');
 const { removeListenedProposal } = require('../../../services/atomic-swap.service');
-const { lockSendTx } = require('../../../helpers/lock.helper');
+const { lockSendTx, getWalletLock } = require('../../../helpers/lock.helper');
 const { cantSendTxErrorMessage } = require('../../../helpers/constants');
 
 /**
@@ -407,7 +407,7 @@ async function unlockInputs(req, res) {
     return;
   }
 
-  const canStart = lock.get(req.walletId).lock(lockTypes.SEND_TX);
+  const canStart = getWalletLock(req.walletId).lock(lockTypes.SEND_TX);
   if (!canStart) {
     res.send({ success: false, error: 'Cannot run this method while a transaction is being sent.' });
     return;
@@ -427,7 +427,7 @@ async function unlockInputs(req, res) {
   } catch (err) {
     res.send({ success: false, error: err.message });
   } finally {
-    lock.get(req.walletId).unlock(lockTypes.SEND_TX);
+    getWalletLock(req.walletId).unlock(lockTypes.SEND_TX);
   }
 }
 
diff --git a/src/helpers/lock.helper.js b/src/helpers/lock.helper.js
index bd03aa15..56e3cbdc 100644
--- a/src/helpers/lock.helper.js
+++ b/src/helpers/lock.helper.js
@@ -6,6 +6,19 @@
  */
 
 const { lock, lockTypes } = require('../lock');
+const { hsmWalletIds } = require('../services/wallets.service');
+
+/**
+ * Get the Lock instance for the given walletID.
+ * @param {string} walletId
+ */
+function getWalletLock(walletId) {
+  if (hsmWalletIds.has(walletId)) {
+    // This is an HSM wallet and the walletLock should be global.
+    return lock.hsmLock;
+  }
+  return lock.get(walletId);
+}
 
 /**
  * Acquire the SEND_TX lock for a wallet and return the method to unlock it.
@@ -15,7 +28,8 @@ const { lock, lockTypes } = require('../lock');
  *
  */
 function lockSendTx(walletId) {
-  const walletLock = lock.get(walletId);
+  const walletLock = getWalletLock(walletId);
+
   const canStart = walletLock.lock(lockTypes.SEND_TX);
   if (!canStart) {
     return null;
@@ -34,4 +48,5 @@ function lockSendTx(walletId) {
 
 module.exports = {
   lockSendTx,
+  getWalletLock,
 };
diff --git a/src/lock.js b/src/lock.js
index d011b9a8..27a00332 100644
--- a/src/lock.js
+++ b/src/lock.js
@@ -78,6 +78,9 @@ class GlobalLock {
     // This is the global lock since some methods are required to be
     // running only once across all wallets.
     this.globalLock = new Lock();
+    // HSM wallets need to share the same send-tx lock because the SDK does not
+    // allow 2 open connections at the same time.
+    this._hsmLock = new Lock();
   }
 
   delete(walletId) {
@@ -103,6 +106,10 @@ class GlobalLock {
   unlock(type) {
     this.globalLock.unlock(type);
   }
+
+  get hsmLock() {
+    return this._hsmLock;
+  }
 }
 
 export const lock = new GlobalLock();