diff --git a/src/background/tabHandler.js b/src/background/tabHandler.js
index 9341c1f..f4bce8e 100644
--- a/src/background/tabHandler.js
+++ b/src/background/tabHandler.js
@@ -84,7 +84,7 @@ export class TabHandler extends Component {
 
     if (this.currentContext && this.currentContext.countryCode) {
       browser.pageAction.setIcon({
-        path: `../assets/flags/${this.currentContext.countryCode}.png`,
+        path: `../assets/flags/${this.currentContext.countryCode.toUpperCase()}.png`,
         tabId: currentTab.id,
       });
       return browser.pageAction.show(currentTab.id);
diff --git a/src/components/vpncard.js b/src/components/vpncard.js
index d1df2f7..dfcb8f1 100644
--- a/src/components/vpncard.js
+++ b/src/components/vpncard.js
@@ -112,7 +112,7 @@ export class VPNCard extends LitElement {
     return html`
       <footer>
         <img
-          src="../../assets/flags/${countryFlag}.png"
+          src="../../assets/flags/${countryFlag.toUpperCase()}.png"
           width="24"
           height="24"
         />
diff --git a/src/ui/browserAction/popupPage.js b/src/ui/browserAction/popupPage.js
index f3e8265..22ecb77 100644
--- a/src/ui/browserAction/popupPage.js
+++ b/src/ui/browserAction/popupPage.js
@@ -269,7 +269,7 @@ export class BrowserActionPopup extends LitElement {
           @click=${openServerList}
         >
           <img
-            src="../../assets//flags/${siteContext.countryCode}.png"
+            src="../../assets//flags/${siteContext.countryCode.toUpperCase()}.png"
             height="24"
             width="24"
           />
diff --git a/src/ui/pageAction/pageAction.js b/src/ui/pageAction/pageAction.js
index 4a28047..e334930 100644
--- a/src/ui/pageAction/pageAction.js
+++ b/src/ui/pageAction/pageAction.js
@@ -66,7 +66,7 @@ export class PageActionPopup extends LitElement {
     const getSrc = () => {
       return excluded
         ? `./../../assets/logos/logo-${scheme}-excluded.svg`
-        : `./../../assets/flags/${this._siteContext?.countryCode}.png`;
+        : `./../../assets/flags/${this._siteContext?.countryCode.toUpperCase()}.png`;
     };
 
     const removeContext = () => {