diff --git a/src/actions/Web3Actions.js b/src/actions/Web3Actions.js
index e1c1b73e..e72ecabb 100644
--- a/src/actions/Web3Actions.js
+++ b/src/actions/Web3Actions.js
@@ -39,6 +39,8 @@ export type Web3UpdateGasPriceAction = {
 
 export type Web3Action = {
     type: typeof WEB3.READY,
+} | {
+    type: typeof WEB3.START,
 } | {
     type: typeof WEB3.CREATE,
     instance: Web3Instance
diff --git a/src/services/Web3Service.js b/src/services/Web3Service.js
new file mode 100644
index 00000000..996e9984
--- /dev/null
+++ b/src/services/Web3Service.js
@@ -0,0 +1,28 @@
+/* @flow */
+
+
+import TrezorConnect, { TRANSPORT } from 'trezor-connect';
+import * as WEB3 from 'actions/constants/web3';
+
+import type {
+    Middleware,
+    MiddlewareAPI,
+    MiddlewareDispatch,
+    Action,
+} from 'flowtype';
+
+/**
+ * Middleware
+ */
+const Web3Service: Middleware = (api: MiddlewareAPI) => (next: MiddlewareDispatch) => (action: Action): Action => {
+    // pass action
+    next(action);
+
+    if (action.type === WEB3.START) {
+        api.dispatch(WalletActions.clearUnavailableDevicesData(prevState, action.device));
+    }
+
+    return action;
+};
+
+export default Web3Service;
\ No newline at end of file
diff --git a/src/services/index.js b/src/services/index.js
index b2ed5a5b..d8aef7c9 100644
--- a/src/services/index.js
+++ b/src/services/index.js
@@ -4,6 +4,7 @@ import RouterService from './RouterService';
 import LocalStorageService from './LocalStorageService';
 import CoinmarketcapService from './CoinmarketcapService';
 import TrezorConnectService from './TrezorConnectService';
+import Web3Service from './Web3Service';
 
 export default [
     WalletService,