diff --git a/app.py b/app.py
index 250a300..ff53512 100644
--- a/app.py
+++ b/app.py
@@ -21,8 +21,8 @@ async def read_and_process_logs() -> dict[tuple[str, str], dict[str, float]]:
     metrics_data: dict[tuple[str, str], dict[str, float]] = {}
 
     if os.path.exists(unit_log_file):
-        async with aiofiles.open(unit_log_file, mode="r+") as f:
-            lines: list[str] = await f.readlines()
+        async with aiofiles.open(unit_log_file, mode="rb+") as f:
+            lines: list[bytes] = await f.readlines()
             await f.truncate(0)
 
         for line in lines: