diff --git a/src/app.ts b/src/app.ts
index 2155df2..50bdfa1 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -83,7 +83,9 @@ async function removeExcessRoomMembers() {
           )
           const memberMapping = await getMappingByMatrixId(actualMember)
           if (!memberMapping || !memberMapping.accessToken) {
-            throw new Error(`Could not find access token for member ${actualMember}, this is a bug`)
+            throw new Error(
+              `Could not find access token for member ${actualMember}, this is a bug`
+            )
           }
 
           await axios.post(
diff --git a/src/helpers/logger.ts b/src/helpers/logger.ts
index 47fd52f..72d3313 100644
--- a/src/helpers/logger.ts
+++ b/src/helpers/logger.ts
@@ -8,10 +8,12 @@ export default winston.createLogger({
       filename: 'warn.log',
       level: 'warn',
       silent: process.env.NODE_ENV === 'test',
+      options: { flags: 'w' },
     }),
     new winston.transports.File({
       filename: 'combined.log',
       silent: process.env.NODE_ENV === 'test',
+      options: { flags: 'w' },
     }),
   ],
   format: winston.format.combine(