diff --git a/tests/common/fixtures.rs b/tests/common/fixtures.rs
index 562ed154..f96b03dd 100644
--- a/tests/common/fixtures.rs
+++ b/tests/common/fixtures.rs
@@ -1,3 +1,4 @@
+use aquatic_udp_protocol::TransactionId;
 use bittorrent_primitives::info_hash::InfoHash;
 
 #[allow(dead_code)]
@@ -20,3 +21,9 @@ pub fn random_info_hash() -> InfoHash {
 
     InfoHash::from_bytes(&random_bytes)
 }
+
+/// Returns a random transaction id.
+pub fn random_transaction_id() -> TransactionId {
+    let random_value = rand::Rng::gen::<i32>(&mut rand::thread_rng());
+    TransactionId::new(random_value)
+}
diff --git a/tests/servers/udp/contract.rs b/tests/servers/udp/contract.rs
index ddccf4f9..9618bef6 100644
--- a/tests/servers/udp/contract.rs
+++ b/tests/servers/udp/contract.rs
@@ -118,8 +118,8 @@ mod receiving_an_announce_request {
     use torrust_tracker_configuration::DEFAULT_TIMEOUT;
     use torrust_tracker_test_helpers::configuration;
 
-    use crate::common::fixtures::random_info_hash;
-    use crate::common::logging;
+    use crate::common::fixtures::{random_info_hash, random_transaction_id};
+    use crate::common::logging::{self, logs_contains_a_line_with};
     use crate::servers::udp::asserts::is_ipv4_announce_response;
     use crate::servers::udp::contract::send_connection_request;
     use crate::servers::udp::Started;
@@ -235,8 +235,6 @@ mod receiving_an_announce_request {
             Err(err) => panic!("{err}"),
         };
 
-        let tx_id = TransactionId::new(123);
-
         // The eleven first requests should be fine
 
         let invalid_connection_id = ConnectionId::new(0); // Zero is one of the not normal values.
@@ -245,11 +243,23 @@ mod receiving_an_announce_request {
 
         for x in 0..=10 {
             tracing::info!("req no: {x}");
+
+            let tx_id = random_transaction_id();
+
             send_and_get_announce(tx_id, invalid_connection_id, info_hash, &client).await;
+
+            let transaction_id = tx_id.0.to_string();
+
+            assert!(
+                logs_contains_a_line_with(&["ERROR", "UDP TRACKER", &transaction_id.to_string()]),
+                "Expected logs to contain: ERROR ... UDP TRACKER ... transaction_id={transaction_id}"
+            );
         }
 
         // The twelfth request should be banned (timeout error)
 
+        let tx_id = random_transaction_id();
+
         let announce_request = build_sample_announce_request(
             tx_id,
             invalid_connection_id,
@@ -257,6 +267,7 @@ mod receiving_an_announce_request {
             info_hash,
         );
 
+        // This should return a timeout error
         match client.send(announce_request.into()).await {
             Ok(_) => (),
             Err(err) => panic!("{err}"),