diff --git a/pyproject.toml b/pyproject.toml
index 296cd79..7ea1e0d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,7 +34,7 @@ opentelemetry-instrumentation-requests = "^0.46b0"
 opentelemetry-instrumentation-fastapi = "^0.46b0"
 wcwidth = "<=0.2.12"
 azure-monitor-opentelemetry = "^1.6.0"
-protobuf = "^4.25.3" # FIXME: update to ^5.27.2 after opentelemetry is updated (see README.md/Protobuf)
+protobuf = "^3.20"
 aio-pika = "^9.4.2"
 aiohttp = "^3.9.5"
 tenacity = "^8.5.0"
@@ -80,7 +80,7 @@ disable = [
     "R0904",
     "R0913",
     "R0914",
-    "W0511"
+    "W0511",
 ]
 docstring-min-length = 3