diff --git a/lib/plugins.js b/lib/plugins.js
index 3080f681..c06da71a 100644
--- a/lib/plugins.js
+++ b/lib/plugins.js
@@ -227,7 +227,7 @@ function plugins (settings, deviceId) {
     }
   }
 
-  function pollQueries (serialNumber, deviceTime, deviceRec, machineVersion, machineModel) {
+  function pollQueries (deviceTime, deviceRec, machineVersion, machineModel) {
     const localeConfig = configManager.getLocale(deviceId, settings.config)
     const fiatCode = localeConfig.fiatCurrency
     const cryptoCodes = localeConfig.cryptoCurrencies
diff --git a/lib/routes/pollingRoutes.js b/lib/routes/pollingRoutes.js
index a2ca4847..b43008bb 100644
--- a/lib/routes/pollingRoutes.js
+++ b/lib/routes/pollingRoutes.js
@@ -61,7 +61,6 @@ function poll (req, res, next) {
   const machineModel = req.query.model
   const deviceId = req.deviceId
   const deviceTime = req.deviceTime
-  const serialNumber = req.query.sn
   const pid = req.query.pid
   const settings = req.settings
   const operatorId = res.locals.operatorId
@@ -85,7 +84,7 @@ function poll (req, res, next) {
 
   state.pids = _.update(operatorId, _.set(deviceId, { pid, ts: Date.now() }), state.pids)
 
-  return Promise.all([pi.pollQueries(serialNumber, deviceTime, req.query, machineVersion, machineModel), triggersPromise, triggersAutomationPromise])
+  return Promise.all([pi.pollQueries(deviceTime, req.query, machineVersion, machineModel), triggersPromise, triggersAutomationPromise])
     .then(([results, triggers, triggersAutomation]) => {
       const cassettes = results.cassettes