diff --git a/src/routes/channels/message_send.rs b/src/routes/channels/message_send.rs
index d83e9a38..8285c885 100644
--- a/src/routes/channels/message_send.rs
+++ b/src/routes/channels/message_send.rs
@@ -31,7 +31,7 @@ pub struct Data {
 
 lazy_static! {
     // ignoring I L O and U is intentional
-    static ref RE_ULID: Regex = Regex::new(r"<@([0-9A-HJKMNPQRSTVWXYZ]{26})>").unwrap();
+    static ref RE_ULID: Regex = Regex::new(r"<@([0-9A-HJKMNP-TV-Z]{26})>").unwrap();
 }
 
 #[post("/<target>/messages", data = "<message>")]