diff --git a/src/components/views/messages/CallEvent.tsx b/src/components/views/messages/CallEvent.tsx
index c0be3b46bb..534458e75b 100644
--- a/src/components/views/messages/CallEvent.tsx
+++ b/src/components/views/messages/CallEvent.tsx
@@ -138,7 +138,7 @@ export default class CallEvent extends React.Component<IProps, IState> {
             } else if (hangupReason === CallErrorCode.UserBusy) {
                 reason = _t("The user you called is busy.");
             } else {
-                reason = _t('Unknown failure: %(reason)s)', { reason: hangupReason });
+                reason = _t('Unknown failure: %(reason)s', { reason: hangupReason });
             }
 
             return (
diff --git a/src/i18n/strings/en_EN.json b/src/i18n/strings/en_EN.json
index f081ec823b..538eb74954 100644
--- a/src/i18n/strings/en_EN.json
+++ b/src/i18n/strings/en_EN.json
@@ -1849,7 +1849,7 @@
     "Their device couldn't start the camera or microphone": "Their device couldn't start the camera or microphone",
     "An unknown error occurred": "An unknown error occurred",
     "No answer": "No answer",
-    "Unknown failure: %(reason)s)": "Unknown failure: %(reason)s)",
+    "Unknown failure: %(reason)s": "Unknown failure: %(reason)s",
     "This call has failed": "This call has failed",
     "You missed this call": "You missed this call",
     "Call back": "Call back",