diff --git a/server/src/handlers/event.rs b/server/src/handlers/event.rs
index 368ac51ef..c0df0570e 100644
--- a/server/src/handlers/event.rs
+++ b/server/src/handlers/event.rs
@@ -33,7 +33,7 @@ use crate::utils::{self, merge};
 
 const PREFIX_TAGS: &str = "x-p-tags-";
 const PREFIX_META: &str = "x-p-meta-";
-const SEPARATOR: char = ',';
+const SEPARATOR: char = '^';
 
 pub async fn query(_req: HttpRequest, json: web::Json<Value>) -> HttpResponse {
     let json = json.into_inner();
diff --git a/server/src/utils.rs b/server/src/utils.rs
index 4563eeff7..c5776aa09 100644
--- a/server/src/utils.rs
+++ b/server/src/utils.rs
@@ -90,7 +90,7 @@ pub mod header_parsing {
             return Err(ParseHeaderError::MaxHeadersLimitExceeded);
         }
 
-        Ok(labels.join(","))
+        Ok(labels.join(&kv_separator.to_string()))
     }
 
     #[derive(Debug, thiserror::Error)]