diff --git a/src/api/ruma_wrapper/axum.rs b/src/api/ruma_wrapper/axum.rs
index f061856f..73a75b3d 100644
--- a/src/api/ruma_wrapper/axum.rs
+++ b/src/api/ruma_wrapper/axum.rs
@@ -60,7 +60,11 @@ where
             )
             .await
             .map_err(|err| {
-                if std::error::Error::source(&err).as_ref().and_then(|err| std::error::Error::source(err)).is_some() {
+                if std::error::Error::source(&err)
+                    .as_ref()
+                    .and_then(|err| std::error::Error::source(err))
+                    .is_some_and(|err| err.is::<http_body_util::LengthLimitError>())
+                {
                     Error::BadRequest(ErrorKind::TooLarge, "Reached maximum request size")
                 } else {
                     Error::BadRequest(ErrorKind::Unknown, "An unknown error has occurred")